Vitamin D and Calcium Supplements Did Not Lower Fracture Risk In Community-Dwelling Adults

MedicalResearch.com Interview with:
“ZMA och D-vitamin. Intages med dubbelsidig C-brus. #placebomannen” by Robin Danehav is licensed under CC BY 2.0Dr Jia-Guo Zhao

Tianjin Hospital
Department of Orthopaedic Surgery
Tianjin, China

MedicalResearch.com: What is the background for this study?

Response: The increased social and economic burdens for osteoporotic-related fractures worldwide make its prevention a major public health goal.

Calcium and vitamin D supplements have long been considered a basic intervention for the treatment and prevention of osteoporosis. Survey analysis showed that 30–50% of older people take calcium or vitamin D supplements in some developed countries. Many previously published meta-analyses, from the high-ranking medical journals, concluded that calcium and vitamin D supplements reduce the incidence of fracture in older adults. And many guidelines regarding osteoporosis recommend calcium and vitamin D supplements for older people. The final aim for these supplements is to prevent the incidence of osteoporotic-related fracture in osteoporosis management.

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Vitamin D May Have a Role In Reducing Risk of Severe Asthma Attacks

MedicalResearch.com Interview with:

David Jolliffe, PhD Centre for Primary Care and Public Health Blizard Institute Barts and the London School of Medicine and Dentistry London

Dr. Jolliffe

David Jolliffe, PhD
Centre for Primary Care and Public Health
Blizard Institute
Barts and the London School of Medicine and Dentistry
London

MedicalResearch.com: What is the background for this study?

Response: Asthma affects more than 300 million people worldwide and is estimated to cause almost 400,000 deaths annually. Asthma deaths arise primarily during episodes of acute worsening of symptoms, known as attacks or ‘exacerbations’, which are commonly triggered by viral upper respiratory infections. Vitamin D is thought to protect against such attacks by boosting immune responses to respiratory viruses and dampening down harmful airway inflammation.

Several clinical trials have tested whether vitamin D supplementation might protect against asthma attacks, but individually their results are inconclusive. In the current study, we pooled raw data from 955 asthma patients who took part in 7 separate trials, which allowed us to answer two questions:

1, Does vitamin D protects against asthma attacks overall, when data from all trials are pooled?

2, Do people who have lower vitamin D levels to start with particularly benefit from supplementation?

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High Dose Vitamin D No Advantage In Preventing Pediatric Viral Infections

MedicalResearch.com Interview with:

Jonathon Maguire MD MSc FRCPC Scientist, Li Ka Shing Knowledge Institute

Dr. Maguire

Jonathon Maguire MD MSc FRCPC
Scientist, Li Ka Shing Knowledge Institute
Staff Pediatrician, Department of Pediatrics, St. Michael’s Hospital

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Vitamin D has been hypothesized as being protective of seasonal viral upper respiratory tract infections.  In this randomized clinical trial, high dose wintertime vitamin D supplementation (2000 IU/day) was compared with standard-dose vitamin D supplementation (400 IU/day) among 703 children.  The number of laboratory confirmed viral upper respiratory tract infections was not statistically different between groups.

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Vitamin D Supplements Will Probably Not Help Asthma or Atopic Dermatitis

MedicalResearch.com Interview with:

Brent Richards, MD, MSc</strong> Associate Professor of Medicine William Dawson Scholar / FRQS Clinical Research Scholar Departments of Medicine, Human Genetics, Epidemiology and Biostatistics McGill University Senior Lecturer, King's College London (Honorary)

Dr. Brent Richards

Brent Richards, MD, MSc
Associate Professor of Medicine
William Dawson Scholar / FRQS Clinical Research Scholar
Departments of Medicine, Human Genetics, Epidemiology and Biostatistics McGill University
Senior Lecturer, King’s College London (Honorary)

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Some previous epidemiological studies have suggested that low vitamin D levels are associated with increased rates of asthma, atopic dermatitis—an itchy inflammation of the skin—and elevated levels of IgE, an immune molecule linked to atopic disease (allergies). In our study, we looked at genetic and health data on more than 100,000 individuals from previous large studies to determine whether genetic alterations that are associated with vitamin D levels predispose people to the aforementioned conditions.

We found no statistically significant difference between rates of asthma (including childhood-onset asthma), atopic dermatitis, or IgE levels in people with and without any of the four genetic changes associated with lower levels of 25-hydroxyvitamin D, the form of vitamin D routinely measured in the blood.

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Monthly Doses of Vitamin D Do Not Prevent Cardiovascular Disease

MedicalResearch.com Interview with:
Robert Scragg, MBBS, PhD
School of Population Health
The University of Auckland
Auckland New Zealand

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Interest in a possible role for vitamin D deficiency as a risk factor for cardiovascular disease was stimulated by studies showing a seasonal variation in cardiovascular disease, which is much higher in winter, when body levels of vitamin D are low, than in summer.

Main findings are that bolus monthly doses of vitamin D supplementation do not prevent against cardiovascular disease, even in people with low levels of vitamin D.

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Effect of Vitamin D and Calcium Supplementation on Cancer Incidence in Older Women

MedicalResearch.com Interview with:

Joan M. Lappe, Ph.D., R.N., F.A.A.N. Associate Dean for Research, College of Nursing Criss/Beirne Professor of Nursing Professor of Medicine Creighton University Omaha NE 68131

Dr. Lappe

Joan M. Lappe, Ph.D., R.N., F.A.A.N.
Associate Dean for Research, College of Nursing
Criss/Beirne Professor of Nursing
Professor of Medicine
Creighton University
Omaha NE 68131

MedicalResearch.com: What is the background for this study? What are the main findings?

  • Numerous observational studies show that higher vitamin D intake and serum 25, hydroxyvitamin D [25(OH)D], the functional indicator of vitamin D status, are associated with lower incidence of cancer.
  • However, the scientific fields consider randomized clinical trials (RCT) as a gold standard for testing new interventions for prevention and treatment of disease. In the only RCT of cancer and vitamin D to date with cancer as a primary outcome, the Women’s Health Initiative, postmenopausal women randomly assigned to vitamin D3400 IU/day and calcium 1000 mg/day showed no difference from those assigned to placebo in colorectal cancer incidence. One criticism of that study was that the vitamin D intervention was low, only 400 international units (IU) per day.
  • In our study we found that, in healthy women ages 55 and older with a mean baseline serum 25(OH)D of 33 ng/mL, supplementation with 2000 IU/day of vitamin D3and 1500 mg/day of calcium for four years, compared with placebo, decreased all-type cancer incidence by about 30%, but this did not reach statistical significance. (p value =0.057 and for statistical significance, the p value would need to be less than 0.05.)
  • In a secondary analysis, we re-analyzed the data excluding cancers that developed during the first year of study and were likely present but not diagnosed upon study enrollment. The findings here were that vitamin D and calcium did significantly decrease cancer risk by about 35%.
  • In another secondary analyses, we combined all of the serum 25(OH)D values to determine if higher levels were associated with lower cancer incidence. Here, higher serum 25(OH)D was significantly associated with lower cancer incidence. Persons with serum 25(OH)D of 55 ng/mL had a 35% lower risk of cancer than persons with serum 25(OH)D of 30 ng/mL.  This is especially interesting since current recommendations for sufficient serum 25(OH)D levels are 20 ng/mL (the National Academy of Medicine) and 30 ng/mL (the Endocrine Society).
  • Note that serum 25(OH)D is a better predictor of cancer development than assigning persons to supplement groups. Serum 25(OH)D takes into account poor compliance of the active supplement group with taking supplements, personal use of supplements by the placebo group, dietary vitamin D intake, sunlight exposure, and the variation among persons in absorption and metabolism of the vitamin D supplement.

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Despite Guidelines, Low Proportion of Elderly Hip Fracture Patients Are Consistently Taking Vitamin D

MedicalResearch.com Interview with:

Dr. Sheila Sprague, PhD Assistant Professor, Research Methodologist McMaster University

Dr. Sheila Sprague

Dr. Sheila Sprague, PhD
Assistant Professor, Research Methodologist
McMaster University

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Previous research has found that daily administration of vitamin D is important for maintaining bone homeostasis. There has been an increased interest among the orthopaedic community regarding vitamin D supplementation and patient outcomes following fractures. Using data from the FAITH trial (NCT01908751), a multicenter randomized controlled trial that compared cancellous screws versus sliding hip screws in patients over the age of 50 with femoral neck fractures, we:

1) determined the proportion of patients consistently taking vitamin D following hip fracture surgery and
2) determined if supplementation was associated with improved health related quality of life and reduced re-operation.

Patients enrolled in the FAITH trial were recruited from 81 clinical sites in 8 countries over a 6-year span. We asked a subset of them about vitamin D supplementation and categorized them as consistent users, inconsistent users, or non-users.

The final analysis included 573 patients and we found that a surprisingly low proportion of elderly hip fracture patients are consistently taking vitamin D (18.7% of patients reported never taking vitamin D, 35.6% reported inconsistent use, and 45.7% reported consistent use). We also found that vitamin D was associated with a statistically (p=0.033), but not clinically, significant improvement in health-related quality of life following a hip fracture. Lastly, supplementation was discovered to not be associated with reduced re-operation (p=0.386).

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Vitamin D During Fetal Life and Bone Health in Children at Age 6

MedicalResearch.com Interview with:
Audry H. Garcia PhD

Scientist Department of Epidemiology
Erasmus MC, University Medical Center Rotterdam
Rotterdam, the Netherlands 

MedicalResearch.com: What is the background for this study?

Response: Fetal bone mineralisation requires an adequate transfer of calcium to the fetus by the end of the pregnancy. Considering that vitamin D is required to maintain normal blood concentrations of calcium, adequate 25-hydroxyvitamin D (25[OH]D) concentrations in pregnant women seem to be crucial for bone development of the offspring. Maternal vitamin D deficiency during pregnancy has been associated with abnormal early skeletal growth in offspring and might be a risk factor for decreased bone mass in later life. Several studies have linked vitamin D deficiency in fetal life to congenital rickets, craniotabes, wide skull sutures and osteomalacia. However, the evidence of long-lasting effects of maternal vitamin D deficiency during pregnancy on offspring’s skeletal development is scarce and inconsistent, and has led to contradictory recommendations on vitamin D supplementation during pregnancy.

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Vitamin D May Have Protective Role Against Respiratory Infections

MedicalResearch.com Interview with:
Dr. Adrian R Martineau
B Med Sci DTM&H MRCP PhD
Clinical Professor of Respiratory Infection and Immunity
Centre for Primary Care and Public Health.
Blizard Institute, Barts and The London School of Medicine and Dentistry
Queen Mary, University of London

MedicalResearch.com: What is the background for this study?

Response: In addition to its well-known effects on bone, Vitamin D has also been shown to boost immune responses to viruses and bacteria that cause respiratory infections in lab experiments.

In order to see whether these effects translate into a health benefit, a total of 25 clinical trials of vitamin D supplementation to prevent various respiratory infections have been carried out in around 11,000 people living in 14 different countries over the last decade.

These trials have yielded conflicting results: in some, vitamin D reduced the risk of infections, but in others it did not.

The reason why vitamin D ‘worked’ in some trials, but not in others, has been the subject of much debate.

In order to answer this question, we assembled an international consortium of investigators and compiled the raw data from every trial into a single database containing information from 10,933 people in total. This allowed us to run sub-group analyses to determine whether particular groups of people benefit more from vitamin D supplementation than others.

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Low Vitamin D Linked To Increased Risk of Chronic Headache

MedicalResearch.com Interview with:

Dr-Jyrki-Virtanen.jpg

Dr. Jyrki Virtanen

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Formation of vitamin D in the skin with UVB light from the sun is a main source of vitamin D during summer months, but in the winter months the UVB light is too weak for vitamin D production. Headache prevalence has been suggested to be related to increasing latitude (less UVB light throughout the year) and possibly to be less prevalent during summer (more UVB light), which suggests a possible role for vitamin D exposure.

Some previous small studies have suggested that low serum vitamin D levels might be associated with more frequent headache or migraine. Our study included 2601 men from the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD) from eastern Finland, aged 42-60 years in 1984-1989, which makes it one of the largest studies so far regarding vitamin D and headache.

In our study chronic headache (occurring weakly or daily) was reported by 250 men, and men reporting chronic headache had lower serum vitamin D levels than others.

When we divided the study population into four groups based on their serum vitamin D levels, the group with the lowest levels had over a twofold risk of chronic headache in comparison to the group with the highest levels. Chronic headache was also more frequently reported by men who were examined outside the summer months of June through September.

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Variable Effects of Dairy, Calcium, Vitamin D on Ovarian Cancer Risk in African–American Women

MedicalResearch.com Interview with:

Bo (Bonnie) Qin, Ph.D. Postdoctoral Scholar Rutgers Cancer Institute of New Jersey New Brunswick, NJ 08903

Dr. Bo Qin

Bo (Bonnie) Qin, Ph.D.
Post-Doctoral Associate
Rutgers Cancer Institute of New Jersey
New Brunswick, NJ 08903

MedicalResearch.com: What is the background for this study?
Response: Ovarian cancer is the leading cause of death from gynecologic cancer in the US. African-American patients diagnosed with ovarian cancer tend to have a worse 5-year survival rate compared to their European-American patients. Therefore, identifying preventive factors in African-Americans women is particularly important.

African Americans tend to consume less calcium and vitamin D from dietary sources, due to a higher prevalence of lactose intolerance, and supplemental intake. Meanwhile, darker color of the skin reduces the synthesis of vitamin D upon sun exposure. They together place African-American women at risk for calcium and vitamin D deficiency. It remains unknown whether calcium, vitamin D, lactose and dairy products are associated with ovarian cancer risk in African-American women and our study aimed to answer this question.

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Can Vitamin D Reduce Insulin Resistance in Muscles of Type 2 Diabetics?

Elisa Benetti, PhD

Elisa Benetti, PhD

MedicalResearch.com Interview with:
Dr. Elisa Benetti PhD
Department of Drug Science and Technology
University of Turin
Turin, Italy

MedicalResearch.com: What is the background for this study?

Response: The idea for this study comes from the debate on the role of vitamin D supplementation in the prevention or progression of type 2 diabetes (T2DM). Epidemiological data point at a strong association between vitamin D deficiency and T2DM prevalence, however a causal relationship is still lacking.

Here we wanted to explore the effect of vitamin D administration on insulin-sensitivity, particularly focusing on skeletal muscle, which is a crucial tissue in the maintenance of glucose homeostasis and which was suggested to be a tissue target of vitamin D.

Using a murine model of insulin-resistance induced by a High Fat-High Sugar Diet (HFHS), we demonstrated that a vitamin D supplementation (7 μg•kg-1, i.p. three times/week) was able to revert the deleterious effects evoked by the diet, including the increase in body weight and in the HOMA-IR (a parameter of insulin resistance) and the glucose tolerance impairment. Consistently, at the muscle level, vitamin D increased the insulin sensitivity by reducing tissue inflammation and fat accumulation (myosteatosis).
These effects are due, at least in part, to the inhibition exerted by vitamin D on carboxymethyl-lysine (CML) production, one of the main Advanced Glucose End-products (AGEs), and on its receptor RAGE.

Collectively, our data indicate the ability of vitamin D to reduce the development of muscle insulin resistance, the primary defect in T2DM patients.
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Maternal High Dose Monthly Vitamin D May Be Useful During Breastfeeding

MedicalResearch.com Interview with:

Dr-Ben-Wheeler.jpg

Dr. Ben Wheeler

Dr. Ben Wheeler MB ChB(Otago) DCH CCE FRACP
Senior Lecturer / Paediatrician / Paediatric Endocrinologist
Department of Women’s & Children’s Health : Te Tari Hauora Wāhine me te Tamariki
Dunedin School of Medicine

MedicalResearch.com: What is the background for this study?

Response: Vitamin D is essential for calcium and bone metabolism. It is unique among vitamins in that it is mainly derived from synthesis in the
skin after exposure to UV-B radiation. In the absence of fortification, few foods are rich in vitamin D, including human milk, which contains very low amounts. Breastfeeding infants in higher latitude countries such as New Zealand, much of North America and
Central/Northern Europe are at risk of vitamin D deficiency.

The most profound manifestation of vitamin D deficiency in growing children is rickets, characterized by bone deformities, impaired growth, biochemical abnormalities, and depending on the severity of deficiency, seizures. Studies also identified a number of common factors that potentially affect the risk of rickets, including darker pigmented skin, maternal vitamin D deficiency during pregnancy, season of birth, and age.

A potential alternative strategy to improve the vitamin D status of breastfed infants is high-dose vitamin D supplementation to pregnant and lactating women. This would be attractive from a compliance perspective, promote exclusive breastfeeding, and treat both the mother and her infant.

Thus, the primary aim of this randomized, placebo-controlled study was to determine the effect of two different monthly doses of maternal vitamin D supplementation on the vitamin D status of non–vitamin D–supplemented breastfed infants and their mothers.
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Vitamin D Levels Fall When Estrogen-Containing Birth Control Pills Stopped

MedicalResearch.com Interview with:

Quaker Harmon M.D., Ph.D. Epidemiology Branch National Institute of Environmental Health Sciences Research Triangle Park, NC 27709

Dr. Quaker Harmon

Quaker Harmon M.D., Ph.D.
Epidemiology Branch
National Institute of Environmental Health Sciences
Research Triangle Park, NC 27709

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Vitamin D is important for bone health. In the United States many women are vitamin D deficient. Vitamin D does not naturally occur in many foods, however some foods are fortified with vitamin D. Supplements and sunshine are the most reliable sources of vitamin D.
Previous studies suggested that women using birth control pills containing estrogen had higher levels of vitamin D. These studies were generally small and were not always able to examine important factors such as time spent outside. We were interested in examining the association between hormonal contraception and vitamin D levels in a larger group of women.

We found that women who use estrogen-containing contraception had a 20% increase in their vitamin D levels. This increase was not due to time spent outside or behaviors related to choice of contraception. The magnitude of increase for hormonal contraception was smaller than for regular use of a supplement containing vitamin D.

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Prostate Cancer Genes in African American Men May Be Affected by Vitamin D Supplementation

MedicalResearch.com Interview with:

Gerard (Gary) Hardiman, Ph.D Professor, Department of Medicine Professor Department of Public Health Sciences Bioinformatics Director Center for Genomic Medicine Medical University of South Carolina Charleston, SC 29425

Dr. Gerard Hardiman

Gerard (Gary) Hardiman, Ph.D
Professor, Department of Medicine Professor
Department of Public Health Sciences Bioinformatics Director
Center for Genomic Medicine Medical
University of South Carolina
Charleston, SC 29425

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: There are significant racial disparities in prostate cancer outcomes. The disease disproportionately affects African American men in terms of incidence, morbidity, and mortality, even after adjustment for stage. African American men have a 2- to 3-times increased risk of developing prostate cancer and have a greater mortality rate compared to European American men. We carried out a prospective clinical study aimed at examining the effects of vitamin D3 supplementation at 4,000 IU per day for two months in male subjects who selected surgical removal of the prostate (prostatectomy) as a definitive treatment for their prostate cancer. The primary goal of this study was to examine molecular differences in gene expression patterns relevant to prostate cancer disparities between African American and European American men, and investigate the global effects of vitamin D3 supplementation on the prostate transcriptome. We carried out genome wide expression profiling experiments using high throughput (HT) RNA sequencing. Transcriptional profiles of each of the patient’s tissue samples were generated and systems level analyses were performed.

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Low Vitamin D Linked To Increase Risk of Orthostatic Hypotension

MedicalResearch.com Interview with:
Dr. Nicola Veronese
University of Padova
Department of Medicine – DIMED, Geriatrics Division
Padova, Italy

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: In the last 5 years, some studies investigated the possible association between hypovitaminosis D and orthostatic hypotension. However, all these studies were cross-sectional,  not disentangling if hypovitaminosis D precedes or follows orthostatic hypotension. In our work, we reported that low vitamin D at baseline predict the onset of orthostatic hypotension at follow-up in older people. This association was stronger in women than in men.

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Vitamin D Not A Panacea For Most Medical Conditions

MedicalResearch.com Interview with:

Michael Allan, MD CCFP Professor of Family Medicine and Director of Evidence Based Medicine Faculty of Medicine & Dentistry University of Alberta

Dr. Mike Allan

Michael Allan, MD CCFP
Professor of Family Medicine and
Director of Evidence Based Medicine
Faculty of Medicine & Dentistry
University of Alberta

MedicalResearch.com: What is the background for this study?

Dr. Allan: A large volume of observational (lower-level) research links lower Vitamin D levels with a long list of health concerns. Other non-clinical studies show the biochemical and physiological actions of Vitamin D could impact many health states. These factors have led many clinicians and scientists to advocate strongly for Vitamin D supplementation. However, this type of research can draw false connections. Therefore, we must examine high-quality randomized studies to determine if Vitamin D supplement can help people live longer, have improved health or avoid negative health outcomes.

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Lack of Sunny Holidays in Northern Latitudes Linked to Low Vitamin D

MedicalResearch.com Interview with:
Ms Emily Weiss PhD student
Centre for Population Health Sciences
The University of Edinburgh

MedicalResearch.com: What is the background for this study? What are the main findings? 

Response: Vitamin D deficiency, a marker of low ultraviolet (UV) exposure, is common in Scotland; both have been shown to work independently as risk factors for multiple sclerosis (MS). Orkney, situated to the north of mainland Scotland has a very high prevalence of MS. We therefore wanted to understand how vitamin D in Orkney compares to mainland Scotland’s vitamin D, and also what may be determining vitamin D levels in Orkney.
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Muscle Enhanced, Fat Reduced When Infants Have Normal Vitamin D Stores

MedicalResearch.com Interview with:

Hope Weiler, RD (CDO), PhD Associate Professor Canada Research Chair tier I, Nutrition and Health Across the Lifespan, Director, Mary Emily Clinical Nutrition Research Unit School of Dietetics and Human Nutrition McGill University Macdonald Campus Ste Anne de Bellevue, QC

Dr. Hope Weiler

Hope Weiler, RD (CDO), PhD
Associate Professor
Canada Research Chair tier I, Nutrition and Health Across the Lifespan,
Director, Mary Emily Clinical Nutrition Research Unit
School of Dietetics and Human Nutrition
McGill University Macdonald Campus
Ste Anne de Bellevue, QC 

MedicalResearch.com: What is the background for this study? What are the main findings?

Dr. Weiler: Vitamin D is a fat soluble with important functions in growth during infancy and childhood, especially for the skeleton. It is for this reason that many policy recommendations for infants stipulate that newborn infants receive a supplemental form of vitamin D. In Canada, it is recommended by Health Canada (www.hc-sc.gc.ca) that newborn infants receive 400 international units of vitamin D from birth to a year of age or until that amount can be obtained from diet. In Canada, older children and adults can make vitamin D when their skin is exposed to direct sunlight between April and October; however, parents are advised to avoid placing their infants in direct sunlight. Thus supplemental vitamin D is particularly important in infancy.

Often newborn infants begin life with low body stores of vitamin D (Weiler and colleagues, CMAJ 2005). This prompted Dr. Weiler’s research group at McGill University to test how much vitamin D is needed by newborn infants in Canada. They learned that 400 to 1200 international units of vitamin D given daily to healthy term born infants is enough to support healthy bone growth and mineral deposition (Gallo and colleagues, JAMA 2013). In conducting tests of bone health, they also learned that the amount of muscle was enhanced and fat reduced when infants had very good vitamin D stores. Vitamin D stores are reflected in the blood. Blood concentrations of a vitamin D form called 25-hydroxyvitamin D are used to establish if stores are in a healthy range. In the recent study published in Pediatric Obesity by Hazell et al, values above 75 nanomoles per litre of blood plasma were linked to lower amounts of body fat (~450 g) at 3 years of age. The 450 g difference is almost a pound of fat. This is a meaningful amount to young children where typical amounts of body fat are 10-times that equating to 4.5 kg (almost 10 pounds). Thus the lower fat is still in a healthy range.

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Majority of Black Teens are Vitamin D Deficient Which May Have Epigenetic Consequences

MedicalResearch.com Interview with:

Haidong Zhu, MD, PhD Associate Professor of Pediatrics Georgia Prevention Institute Medical College of Georgia Augusta University

Dr. Haidong Zhu

Haidong Zhu, MD, PhD
Associate Professor of Pediatrics
Georgia Prevention Institute
Medical College of Georgia
Augusta University

MedicalResearch.com: What is the background for this study? What are the main findings?

Dr. Zhu: Vitamin D plays an important role in a wide range of body functions beyond bone health. Vitamin D deficiency is associated with increased risk of cancer and cardiovascular disease. Vitamin D deficiency is common among darker skin individuals, particularly African-Americans, which could contribute to health disparity. We want to understand underlying molecular mechanism (i.e. global DNA methylation) for how vitamin D deficiency causes cancer, cardiovascular disease and impaired immune function. DNA methylation, a chemical modification to our genome, is one of the ways that our body adapts to the environment. Low rate of global DNA methylation is a common event in cancer, which may lead to disturbances in the genome, make the genome more vulnerable to environmental damage and increase disease risk.

Our study shows that majority of black teens are vitamin D deficient and have a lower rate of global DNA methylation than white teens. We further demonstrate that vitamin D3 supplementation for 16 weeks increases global DNA methylation in black teens and young adults. Our study provides an important piece of evidence that vitamin D plays a role in epigenetic regulation in humans, which could be an underlying mechanism for vitamin D-deficiency related disease risk and health disparity.

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Higher Vitamin D Levels Associated With Lower Cancer Risk

MedicalResearch.com Interview with:
Sharon L. McDonnell MPH
GrassrootsHealth
Encinitas, California

Medical Research: What is the background for this study? What are the main findings?

Response: Higher vitamin D levels in the blood have been associated with a lower risk of multiple cancer types including colorectal and breast. Using data from two study cohorts of women aged 55 years and older (N=2,304), we investigated the association between serum 25(OH)D concentration, the marker of vitamin D in the blood, and risk of all non-skin cancers combined across a broad range of 25(OH)D concentrations. We found that women with 25(OH)D concentrations ≥40 ng/ml had a 67% lower risk of cancer compared to women with concentrations <20 ng/ml. We also found that the greatest decrease in risk occurred between ~10-40 ng/ml. These findings suggest that increasing 25(OH)D concentrations to a minimum of 40 ng/ml could substantially reduce  cancer incidence and associated mortality in the population.

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High-dose vitamin D May Improve Heart Function in Some CHF Patients

MedicalResearch.com Interview with:

Dr Klaus Witte MD, FRCP, FESC, FACC Associate Professor and Consultant Cardiologist Lead Clinician for Cardiology University of Leeds and Leeds Teaching Hospitals NHS Trust

Dr. Klaus Witte

Dr Klaus Witte MD, FRCP, FESC, FACC
Associate Professor and Consultant Cardiologist
Lead Clinician for Cardiology
University of Leeds and Leeds Teaching Hospitals NHS Trust 

MedicalResearch.com: What is the background for this study? What are the main findings?

Dr. Witte: Chronic heart failure (CHF) is a condition of heart muscle weakness that despite optimal treatment often leaves patients with ongoing symptoms of breathlessness and fatigue.

Vitamin D has a large number of effects in the body beyond its known effects on the skeleton.

Patients with  Chronic heart failure are frequently deficient in vitamin D, but until now there were no data demonstrating a benefit from supplements.

We conducted a randomised, placebo-controlled study of a non-calcium-based vitamin D supplement providing 4000IU or 100mcg per day of vitamin D3 (VINDICATE).

Endpoints included 6-minute walk distance and cardiac function. We saw no improvement in 6 minute walk distance but a large and significant improvement in heart function (left ventricular ejection fraction) and heart size (left ventricular dimensions and volumes) after on year. We saw no significant adverse effects and the tablets were well tolerated.

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Deeply Tanned Skin May Prevent Optimal Vitamin D Formation

MedicalResearch.com-Interview with:

Francisco Bandeira,M.D.,PhD.,F.A.C.E. Professor of Medicine and Chairman, Division of Endocrinology, Agamenon Magalhães Hospital, University of Pernambuco Medical School

Dr. Francisco Bandeira

Francisco Bandeira,M.D.,PhD.,F.A.C.E.
Professor of Medicine and Chairman, Division of Endocrinology, Agamenon Magalhães Hospital,
University of Pernambuco Medical School

MedicalResearch.com: What is the background for this study? What are the main findings?

Dr. Bandeira: We had the opportunity to evaluate a population with very high rates of sun exposure in daily life at a tropical region with abundant sunlight (UV index of 5 at 7 am and more than 10 at midday). We found that more exposure to the sun, less vitamin D deficiency, so nature “works”. But more sun exposure led to more tanned skins and despite these very high rates of sun exposure, most people were not able to achieve optimal blood levels of 25OHD (> 30 ng/ml).

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Vitamin D Supplements Did Not Slow Knee Cartilage Loss in Osteoarthritis

MedicalResearch.com Interview with:

Changhai Ding, MBBS, MMED, MD Australian Research Council Future Fellow Associate Director (International), Menzies Institute for Medical Research Professor, University of Tasmania, Australia Honorary Professor, University of Sydney, Australia

Dr. Changhai Ding

Changhai Ding, MBBS, MMED, MD
Australian Research Council Future Fellow
Associate Director (International), Menzies Institute for Medical Research
Professor,  University of Tasmania, Australia
Honorary Professor, University of Sydney, Australia

MedicalResearch.com: What is the background for this study? What are the main findings?

Dr. Ding: Vitamin D can reduce bone turnover and cartilage degradation, thus potentially preventing the development and progression of knee osteoarthritis. Observational studies suggest that vitamin D supplementation is associated with benefits for knee osteoarthritis, but current evidence from clinical trials is contradictory.

We  conducted a randomised clinical trial in Hobart, Tasmania and Melbourne, Victoria in Australia. We randomly assigned 413 patients with symptomatic knee osteoarthritis and low 25-hydroxyvitamin D to receive monthly treatment with oral vitamin D3 (50,000 IU; n = 209) or an identical placebo (n = 204) for 2 years.

Of 413 enrolled participants (average age, 63 years; 50 percent women), 340 (82 percent) completed the study. Vitamin D supplementation significantly increased blood 25-hydroxyvitamin D levels over 2 years compared with placebo treatment; however, vitamin D supplementation, compared with placebo, did not result in significant differences in change in MRI-measured tibial cartilage volume or a measure of knee pain over 2 years. There were also no significant differences in change of tibiofemoral cartilage defects or change in tibiofemoral bone marrow lesions.

Post-hoc analyses indicated that vitamin D supplementation might improve knee physical function and reduce another measure of knee pain and increases in bone marrow lesion.

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Vitamin D Deficiency in Pregnancy May Raise Risk of Multiple Sclerosis In Offspring

MedicalResearch.com Interview with:
Kassandra Munger, Sc.D.
Harvard T.H. Chan School of Public Health

MedicalResearch.com: What is the background for this study?

Dr. Munger: Previous work has shown that adequate vitamin D nutrition is associated with a lower risk of multiple sclerosis (MS).  Results from studies examining whether adequate vitamin D exposure during early-life are also associated with a lower risk of MS have been mixed.  One study reported that daughters of mothers with high dietary vitamin D intake during their pregnancy had a reduced risk of multiple sclerosis, while two studies measuring 25-hydroxy vitamin D either in a blood sample from the pregnant mother or from a sample taken from the neonate, were not associated with future multiple sclerosis risk in the child.

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Trial Tests Effect of Vitamin D Supplementation During Pregnancy On Wheezing in Children

More on Asthma on MedicalResearch.com

Professor of Pediatrics Hans Bisgaard, MD, DMSc Copenhagen Prospective Studies on Asthma in Childhood Herlev and Gentofte Hospital, University of Copenhagen, Denmark.

Prof. Bisgaard

MedicalResearch.com Interview with:
Hans Bisgaard, MD, DMSc
Professor of Pediatrics
The Faculty of Health Sciences
University of Copenhagen
Head of the Copenhagen Prospective Studies on Asthma in Childhood
University  of Copenhagen and Naestved Hospital

MedicalResearch: What is the background for this study? What are the main findings?

Dr. Bisgaard: Vitamin D deficiency has become a common health problem in westernized societies, possibly caused by a more sedentary indoor lifestyle and decreased intake of vitamin D containing foods. Vitamin D possesses a range of immune regulatory properties, and it has been speculated that vitamin D deficiency during pregnancy may affect fetal immune programming and contribute to asthma pathogenesis. Asthma often begins in early childhood and is the most common chronic childhood disorder. Observational studies have suggested that increased dietary vitamin D intake during pregnancy may protect against wheezing in the offspring, but the preventive effect of vitamin D supplementation to pregnant women is unknown. In our double-blind, single-center, randomized clinical trial conducted within the Copenhagen Prospective Studies on Asthma in Childhood 2010 cohort we supplemented 2800 IU/d of vitamin D3 during the third trimester of pregnancy compared with 400 IU/d in the control group. Although the maternal supplementation did not result in a statistically significant reduction of risk of persistent wheeze in the offspring through age 3 years, the interpretation of the study is limited by a wide confidence interval that includes a clinically important protective effect.

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Does Prenatal Supplementation With Vitamin D Affect Childhood Asthma?

Augusto A. Litonjua, MD, MPH Associate Professor Channing Division of Network Medicine and Division of Pulmonary and Critical Care Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Boston, MA 02115 USA

Dr. Augusto Litonjua

MedicalResearch.com Interview with:
Augusto A. Litonjua, MD, MPH
Associate Professor
Channing Division of Network Medicine
and Division of Pulmonary and Critical Care Medicine
Department of Medicine
Brigham and Women’s Hospital
Harvard Medical School
Boston, MA 02115 USA 

Medical Research: What is the background for this study? What are the main findings?

Response: Vitamin D deficiency has been hypothesized to contribute to the asthma and allergy epidemic.  Vitamin D has been shown to affect lung development in utero. However, observational studies have shown mixed results when studying asthma development in young children. Since most asthma cases start out as wheezing illnesses in very young children, we hypothesized that vitamin D supplementation in pregnant mothers might prevent the development of asthma and wheezing illnesses in their offspring.  We randomly assigned 881 pregnant women at 10 to 18 weeks’ gestation and at high risk of having children with asthma to receive daily 4,000 IU vitamin D plus a prenatal vitamin containing 400 IU vitamin D (n = 440), or a placebo plus a prenatal vitamin containing 400 IU vitamin D (n = 436). Eight hundred ten infants were born during the study period, and 806 were included in the analyses for the 3-year outcomes. The children born to mothers in the 4,400 IU group had a 20% reduction in the development of asthma or recurrent wheeze compared to the children born to mothers in the 400 IU group (24% vs 30%, respectively; an absolute reduction of 6%).  However, this reduction did not reach statistical significance (p=0.051).

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Vitamin D Status May Influence Bariatric Surgery Outcomes

Leigh A. Peterson, PhD, MHS Post-doctoral fellow Department of Surgery - Bayview Johns Hopkins School of Medicine

Dr. Leigh Peterson

MedicalResearch.com Interview with:
Leigh A. Peterson, PhD, MHS

Post-doctoral fellow
Department of Surgery – Bayview
Johns Hopkins School of Medicine

Medical Research: What is the background for this study? What are the main findings?
Dr. Peterson: From our previous study published in Obesity Surgery earlier this year, we knew that vitamin D deficiency and insufficiency was very common in our bariatric surgery candidates (71.4% < 20 ng/ml and 92.9% < 30 ng/ml). We wanted to explore the effect of this deficiency on adverse outcomes after bariatric surgery such as wound healing, infection, and extended hospital stay.

We turned to the Nationwide Inpatient Sample to answer this question, as it would contain enough surgeries to detect changes in even less frequent outcomes such as wound infection. But blood concentration of vitamin D is not available, so we used a traditional method to estimate group vitamin D status with season and geography. Vitamin D comes from the sun, so people have the most vitamin D in summer and in sunnier places.

In 932,091 records of bariatric surgeries from 2001 to 2010, we saw that more adverse outcomes occurred during winter—January to March, the time of lowest vitamin D status—compared to summer or even spring or fall. Additionally, most adverse outcomes occurred in northern latitudes (≥ 37°N) compared to sunnier southern latitudes.

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Vitamin D Level Likely Has No Impact on Sleep Apnea

Ken M. Kunisaki , MD Associate Professor of Medicine Pulmonary, Allergy, Critical Care and Sleep Medicine University of Minnesota

Dr. Kunisaki

MedicalResearch.com Interview with:
Ken M. Kunisaki , MD
Associate Professor of Medicine
Pulmonary, Allergy, Critical Care and Sleep Medicine
University of Minnesota 

Medical Research: What is the background for this study? What are the main findings?

Dr. Kunisaki : Obstructive sleep apnea (OSA) is a very common condition that is the result of recurrent complete or partial closure of the upper airway during sleep.  OSA leads to poor sleep quality and excessive daytime sleepiness.

A previous study suggested that OSA is more common in the winter, but there were no vitamin D measurements in that study, which seemed potentially relevant since many people have lower vitamin D levels in the winter, due to less sunlight exposure in the winter.  Several studies have also shown that people with low vitamin D levels have worse muscle function.  Since muscles are partially responsible for keeping the upper airway open during sleep, we wondered whether people with low vitamin D levels might have weaker upper airway muscles and therefore be more prone to having OSA.

In our study, we found that indeed, persons with OSA had lower vitamin D levels than those without OSA, but this was explained by obesity.  In other words, the low vitamin D levels seen in OSA patients is likely just a marker of obesity and not likely related to the presence or absence of OSA.
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Vitamin D and May Improve Exercise Performance

Dr Emad Al-Dujaili Reader in Biochemistry and Nutrition, Queen Margaret University Department of Health Science Queen Margaret UniversityMedicalResearch.com Interview with:
Dr Emad Al-Dujaili
Reader in Biochemistry and Nutrition,
Queen Margaret University
Department of Health Science
Queen Margaret University

Medical Research: What is the background for this study? What are the main findings?

Dr. Al-Dujaili: Recent studies have implicated vitamin D deficiency as a risk factor for Cardiovascular disease and its deficiency is a potential biological predictor of increased rates of CVD. We have done 2 earlier studies investigating the effects of Vitamin D intake on Blood pressure and the stress hormone level cortisol and found that people taking the supplement of Vitamin D had reduced systolic and diastolic blood pressure compared to those who took the placebo. Vitamin D deficiency has also been associated with hypertension, obesity, diabetes mellitus and oxidative stress and reduced exercise performance. For instance, the Framingham offspring study proved that low levels of vitamin D are independently related to Cardiovascular disease incidence. In this placebo-controlled study, We have observed that people given 50ug of Vitamin D daily for 2 weeks showed a significantly reduced systolic and diastolic blood pressure, reduced urinary free cortisol (the hormone that produces stress and high blood pressure if its levels are high. Moreover, the distance cycled in 20 minutes significantly increased by 30% with slightly less efforts compared with that before Vitamin D supplement.

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Low Vitamin D Associated With Accelerated Cognitive Decline

Joshua W. Miller, PhD Professor and Chair Dept. of Nutritional Sciences Rutgers The State University of New Jersey New Brunswick, NJ 08901

MedicalResearch.com Interview with:
Joshua W. Miller, PhD

Professor and Chair Dept. of Nutritional Sciences Rutgers
The State University of New Jersey
New Brunswick, NJ 08901 

Medical Research: What is the background for this study? What are the main findings?

Response: In recent years, there has been a growing scientific literature on the associations between low vitamin D status in older adults and risk of Alzheimer’s disease/dementia, cognitive impairment and decline, and brain atrophy.  The vast majority of these studies have been conducted in predominantly white populations.  The relatively unique aspect of our study was that over half of the cohort consisted of African Americans and Hispanics.  What we found in our cohort (mean age ~75y, n=382 at baseline) was that participants with vitamin D deficiency (serum 25-hydroxyvitamin D <12 ng/ml) or vitamin D insufficiency (serum 25-hydroxyvitamin D between 12 ng/ml and <20 ng/ml) on average experienced faster rates of cognitive decline in episodic memory and executive function than participants with adequate vitamin D status.  Importantly, the association between vitamin D status and the rate of decline in cognitive function was independent of race/ethnicity.  However, the prevalence of low vitamin D status in the study participants was significantly higher in the African American and Hispanic participants compared with the White participants.  This is most likely due to the fact that darker skin pigmentation reduces the ability of sunlight to induce vitamin D synthesis in the skin.  It may also reflect differences in dietary intake of vitamin D and supplement use between the different race/ethnicity groups, though we did not assess this in our study.  Thus, though the rate of cognitive decline in African Americans and Hispanics does not seem to be more or less affected by low vitamin D status than in Whites, because African Americans and Hispanics have a higher prevalence of low vitamin D status, as subpopulations they may be more prone to rapid cognitive decline in old age.  Further studies addressing this possibility are needed.

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Vitamin D Did Not Improve Bone or Muscle Health in Post-Menopausal Women

MedicalResearch.com Interview with:
Karen E. Hansen, M.D., M.S.
Associate Professor of Medicine
University of Wisconsin School of Medicine and Public Health
Madison, WI 53705-2281

Medical Research: What is the background for this study?

Dr. Hansen: The USPTF says to older community dwelling adults, “don’t bother taking vitamin D”, the Endocrine Society says “take 2,000-4,000 IU daily” and the Institute of Medicine gave an RDA of 600-800 IU daily. The Endocrine Society argues that optimal vitamin D levels are 30 ng/mL and higher, while the Institute of Medicine concludes that 20 ng/mL and higher indicates optimal vitamin D status. The disagreement between experts prompted my study.

Medical Research: What are the main findings?

Dr. Hansen: Among postmenopausal women whose vitamin D level was ~21 ng/mL at baseline, there was no benefit of high-dose or low-dose vitamin D, compared to placebo, on spine/hip/total body bone mineral density, muscle fitness by 5 sit to stand test or Timed Up and Go, or falls. We did see a small 1% increase in calcium absorption in the high-dose vitamin arm, but this small increase did not translate into clinically meaningful changes in bone density or muscle tests.

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Many US Infants Found To Be Vitamin D Deficient

Katherine Ahrens Ph.D. MPH National Center for Health Statistics Centers for Disease Control and Prevention Hyattsville, MDMedicalResearch.com Interview with:
Katherine Ahrens Ph.D. MPH

National Center for Health Statistics
Centers for Disease Control and Prevention
Hyattsville, MD

Medical Research: What is the background for this study?

Dr. Ahrens: In 2008, the American Academy of Pediatrics (AAP) revised their recommended minimum daily intake of vitamin D for infants and children to 400 IU.

Medical Research: What are the main findings?

Dr. Ahrens: Approximately one quarter of US infants aged 0 to 11 months met the 2008 AAP vitamin D recommendations on a given day in 2009 to 2012. Fewer than 1 in 5 breastfed infants met the vitamin D recommendations compared to nearly 1 in 3 non-breastfed infants. Continue reading

Exercise May Be More Effective Than Vitamin D In Reducing Falls

MedicalResearch.com Interview with:
Kirsti Uusi-Rasi, PhD, Adjunct Professor
Senior Researcher
UKK Institute for Health Promotion Research
Tampere Finland

Medical Research: What is the background for this study? What are the main findings?

Dr. Kirsti Uusi-Rasi: Falls are the leading cause of unintentional injuries and fractures in
older adults, head injuries and fractures being the most severe
consequences. Therefore, falls prevention is important when trying to
prevent injuries. There is strong high-quality evidence from previous
studies that exercise that includes strength and balance training can
reduce the risk of falling in older adults. However, there are also
studies that have reported no benefit in reducing the actual incidence
of falls. Effects of vitamin D have also been studied widely, and
vitamin D is known to be vital for bone metabolism and health.
However, results regarding effects on falls and fractures are
inconsistent. Furthermore, persons with low vitamin D levels (serum
25OHD) have been associated with lower physical performance and
greater decline in physical functioning, but clinical trials exploring
the role of vitamin D in reducing falls and fractures and in improving
physical functioning are inconclusive. Because there is hardly any
evidence about exercise and vitamin D together, we investigated the
separate and combined effects of multimodal exercise training and
vitamin D supplementation in reducing falls and injurious falls among
older women at risk for falling.

We assigned 409 participants randomly to one of four groups with:
1)vitamin D 800 IU/day and exercise
2) placebo and exercise
3) vitamin D 800 IU/day without exercise
4) placebo without exercise.

Exercise consisted of strength, balance, mobility and agility group training.

At the end of two years, exercise seemed to be more effective in
reducing injurious falls in this age group, with or without vitamin D.
Exercise also improved physical functioning (strength, balance and
mobility). In general, the training program was well tolerated with no
severe adverse effects or injuries. Vitamin D helped maintain femoral
neck BMD and increased trabecular bone density at the tibia. Our study
also suggests that the current vitamin D recommendation (800 IU/d for
older people) is adequate.

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Women With Low Vitamin D More Likely To Report Depression

David C.R. Kerr Ph.D. Sch of Psychological Science Associate Professor College of Liberal Arts Oregon State UniversityMedicalResearch.com Interview with:
David C.R. Kerr Ph.D.
Sch of Psychological Science Associate Professor
College of Liberal Arts Oregon State University

Medical Research: What is the background for this study? What are the main findings?

Dr. Kerr: Many people assume we already know that low levels of vitamin D contribute to depression, especially in winter. However, studies have not found consistent evidence for this, and most studies have focused on people in late life or with serious medical conditions. We focused on apparently healthy young women living in the Pacific Northwest. We found that women with low blood levels of vitamin D were more likely to report clinically significant depressive symptoms. This link existed even when we considered other factors that might explain both problems, such as diet, obesity, and time of year. Continue reading

Genetic Vitamin D Metabolism Linked To Fatal Prostate Cancer

Irene Shui ScD MPH Staff Scientist Fred Hutchinson Cancer Research Center Seattle, WA 98109MedicalResearch.com Interview with
Irene Shui ScD MPH
Staff Scientist
Fred Hutchinson Cancer Research Center
Seattle, WA 98109

MedicalResearch: What is the background for this study? What are the main findings?

Dr. Shui: Given the high prevalence of prostate cancer and the wide international variation in vitamin D status, identifying causal links between the two could have a large public health impact. Evidence from experimental animal and cell line studies support anti-cancer properties of vitamin D. However, the results from human epidemiologic studies for prostate cancer risk have been equivocal. Few studies have addressed risk of fatal prostate cancer prostate cancer. One recent study reported a 57% reduction in the risk of fatal prostate cancer in men with the highest vs. lowest vitamin D levels.  The purpose of this study was to follow-up on these findings in a large cohort consortium with over 500 cases of fatal prostate cancer.

MedicalResearch: What should clinicians and patients take away from your report?

Dr. Shui: We did not find consistent evidence among 5 cohort studies to support an increased or decreased risk of dying from prostate cancer based on a man’s levels of circulating vitamin D. However, we observed some evidence that common genetic variation in genes involved in vitamin D metabolism and signaling may modify this association. Patients should discuss their vitamin D status with their health care provider as it is important for bone health, immune function, and may prevent other diseases.

MedicalResearch: What recommendations do you have for future research as a result of this study?

Dr. Shui: Studies of Vitamin D should consider if variation in genes involved in vitamin D metabolism and signaling could modify disease associations.

Citation:

Shui, I. M., Mondul, A. M., Lindström, S., Tsilidis, K. K., Travis, R. C., Gerke, T., Albanes, D., Mucci, L. A., Giovannucci, E., Kraft, P. and for the Breast and Prostate Cancer Cohort Consortium Group (2015), Circulating vitamin D, vitamin D–related genetic variation, and risk of fatal prostate cancer in the National Cancer Institute Breast and Prostate Cancer Cohort Consortium. Cancer. doi: 10.1002/cncr.29320

MedicalResearch.com Interview with, Irene Shui ScD MPH (2015). Genetic Vitamin D Metabolism Linked To Fatal Prostate Cancer 

Low Vitamin D in Childhood Linked To Early Atherosclerosis

MedicalResearch.com Interview with:
Markus Juonala, MD, PhD
University of Turku Finland

Medical Research: What is the background for this study? What are the main findings?

Response: Earlier studies suggest that low vitamin D levels may be associated with cardiovascular disease. We wanted to study whether low childhood vitamin levels predict carotid intima-media thickness, a marker of early atherosclerosis, in adulthood. We observed that those children with vitamin D in lowest quartile had increased risk for high carotid intima-media thickness.

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Genetically Low Vitamin D Levels Linked To Increased Mortality

MedicalResearch.com Interview with:
Børge G Nordestgaard, MD, DMSc

Professor, University of Copenhagen
Chief Physician, Herlev Hospital, Copenhagen University Hospital
Dept. Clinical Biochemistry Herlev Ringvej Herlev, Denmark

Medical Research: What is the background for this study? What are the main findings?

Prof. Nordestgaard: Many people take vitamin D supplements with the hope of reducing morbidity and mortality. However, it is unclear whether low vitamin D per se is a direct cause of increased mortality or whether it is simply a marker of poor lifestyle in general and/or underlying hidden disease. Our study involved 95,766 white participants of Danish descent from three cohorts in Copenhagen, who had genetic variants known to affect vitamin D levels. We found that genetically low vitamin D levels were associated with increased all-cause mortality, cancer mortality, and other mortality, but not with cardiovascular mortality. This is important as such genetics studies cannot be explained by poor lifestyle or hidden disease, as neither can change your genes.

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Vitamin D Levels Lower In Children Who Drink Non-Cow’s Milk

Jonathon Maguire MD MSc FRCPC Pediatrician and Scientist  Department of Pediatrics Li Ka Shing Knowledge Institute St. Michael’s Hospital University of TorontoMedicalResearch.com: Interview with:
Jonathon Maguire MD MSc FRCPC
Pediatrician and Scientist  Department of Pediatrics
Li Ka Shing Knowledge Institute
St. Michael’s Hospital University of Toronto

 

Medical Research: What is the background for this study? What are the main findings?

Dr. Maguire: One of the main health benefits of cow’s milk is vitamin D.  We were interested to know if non-cow’s milk supports children’s vitamin D blood levels as well as cow’s milk.
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Vitamin D: No Causal Link With Type 2 Diabetes

Dr Nita Forouhi Lead Scientist and Programme Leader MRC Epidemiology Unit University of Cambridge School of Clinical MedicineMedicalResearch.com Interview with:
Dr Nita Forouhi, MRCP, PhD, FFPHM
Lead Scientist and Programme Leader
MRC Programme Leader and Consultant Public Health Physician
MRC Epidemiology Unit
University of Cambridge School of Clinical Medicine
Cambridge Biomedical Campus Cambridge, UK

Medical Research: What are the main findings of the study?

Dr. Forouhi: This large study found that low blood concentrations of 25-hydroxyvitamin D [25(OH)D], a clinical indicator of vitamin D status, were associated with an increased risk of type 2 diabetes, but this did not appear to be a cause-effect relationship. To investigate these associations, we did two things. We first did a systematic review and meta-analysis across 22 published studies and confirmed that there was a strong inverse relation between vitamin D levels and the risk of future new-onset type 2 diabetes among people who did not initially have diabetes. We then used a genetic approach, called Mendelian randomisation, which allows us to test a cause-effect relationship, and found that genetically lower vitamin D levels were not related to risk of type 2 diabetes. This means that we were able to distinguish between association and causation, and concluded that the vitamin D levels did not have a causal link with type 2 diabetes. Continue reading

Effect of High-Dose Vitamin D Supplementation In Critically Ill Patients

Karin Amrein, MD, MSc Assistant Professor Department of Internal Medicine Division of Endocrinology and Metabolism Medical University of Graz 8036 Graz, AustriaMedicalResearch.com Interview with:
Karin Amrein, MD, MSc
Assistant Professor Department of Internal Medicine
Division of Endocrinology and Metabolism
Medical University of Graz
8036 Graz, Austria

Medical Research: What are the main findings of the study?

Dr. Amrein: This is the first large clinical trial on vitamin D in critical care. In a double-blind, randomized, placebo-controlled clinical trial, a population of mixed adult ICU patients with vitamin D deficiency (defined as 25-hydroxyvitamin D [25(OH)D] level ≤ 20ng/ml) was assigned to receive either vitamin D3 or placebo. We used a high loading dose of vitamin D3 followed by monthly maintenance doses of 90,000 IU for a total of 5 months. Because of a substantially increased risk for skeletal complications below 12ng/ml of 25-hydroxyvitamin D, we used this threshold for a predefined subgroup analysis.

Overall, high-dose vitamin D3 compared with placebo did not reduce hospital length of stay (primary endpoint), intensive care unit (ICU) length of stay, hospital mortality, or 6 month-mortality

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Study Questions Supplemental Vitamin D for Heart Disease Prevention

MedicalResearch.com Interview with
Esther Ooi &
Børge G Nordestgaard, MD, DMSc
Professor, University of Copenhagen
Chief Physician, Herlev Hospital, Copenhagen University Hospital
Dept. Clinical Biochemistry Herlev Ringvej 75, DK-2730 Herlev, Denmark

Medical Research: What are the main findings of the study?

Answer: Our findings suggest that low 25(OH)D levels observationally is simply a marker for elevated atherogenic lipoproteins, and thus question a role for vitamin D supplementation in the prevention of cardiovascular disease.
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Study Examines Vitamin D and Cancer Prognosis

Adetunji Toriola, MD, PhD, MPH  Assistant Professor Division of Public Health Sciences Department of Surgery Washington University School of Medicine Siteman Cancer Center St. Louis, MO MedicalResearch.com Interview with:
Adetunji Toriola, MD, PhD, MPH
Assistant Professor Division of Public Health Sciences
Department of Surgery
Washington University School of Medicine
Siteman Cancer Center St. Louis, MO

MedicalResearch: What are the main findings of the study?

Dr. Toriola: Very little is known about the impact of vitamin D in prognosis among cancer patients. This knowledge is of importance because of the increasing number of people living cancer and the high prevalence of vitamin D deficiency among cancer patients. We conducted a systematic review of studies published to date on the association of circulating vitamin D (25-OHD) levels with prognosis among cancer patients. This review suggests that higher circulating vitamin D levels may improve overall survival among breast and colorectal cancer patients but there is paucity of information on the role of circulating vitamin D levels in prognosis among patients with other cancer types.

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Vitamin D Linked to Better Outcomes in Several Types of Cancer

Hui Wang, M.D., Ph.D., Professor Principal Investigator Director, Food Safety Research Center Institute for Nutritional Sciences, SIBS, CASMedicalResearch.com Interview with:
Hui Wang, M.D., Ph.D., Professor
Principal Investigator
Director, Food Safety Research Center
Institute for Nutritional Sciences, SIBS, CAS


MedicalResearch.com: What are the main findings of the study?


Dr. Wang: 
This meta-analysis has systematically reviewed 25 relevant studies composed of 17,332 cancer cases to give a comprehensive perspective on the relationship between vitamin D and cancer patient outcomes. Our result demonstrated that vitamin D levels are linked to better outcomes in several types of cancer patients. The strongest link was found in breast cancer, lymphoma and colorectal cancer. There was less evidence of a connection in people with lung cancer, gastric cancer, prostate cancer, leukemia, melanoma or Merkel cell carcinoma, but the available data were positive. We also found that a 10 nmol/L increase in vitamin D levels was tied to a 4 percent increase in survival among people with cancer.

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Calcium – Vitamin D Supplementation: Effect on Heart Disease and Mortality?

Joshua Lewis, Ph.D Raine Foundation / Alan Robson Fellow Bone and Vascular Research Group School of Medicine and Pharmacology University of Western Australia Department of Endocrinology and Diabetes Sir Charles Gairdner HospitalMedicalResearch.com Interview with:
Joshua Lewis, Ph.D
Raine Foundation / Alan Robson Fellow
Bone and Vascular Research Group
School of Medicine and Pharmacology
University of Western Australia
Department of Endocrinology and Diabetes
Sir Charles Gairdner Hospital

MedicalResearch.com: What are the main findings of the study?

Dr. Lewis: We tested the hypothesis raised by others that calcium supplementation with or without vitamin D increases coronary heart disease and mortality risk in elderly women. To do this we undertook a meta-analysis of published and unpublished data from patient level and cluster randomized controlled trials of calcium supplements with or without vitamin D in elderly women. Importantly all events included in this large meta-analysis were verified by clinical review, hospital record or death certificate. We did not observe any significant increase in all-cause mortality or coronary heart disease events that included myocardial infarction, angina pectoris and acute coronary syndromes and chronic coronary heart disease.
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Vitamin D Did Not Alter Risk of Falls

MedicalResearch.com Interview with:
Dr Mark Bolland, PhD
Bone and Joint Research Group, Department of Medicine
University of Auckland, Auckland, New Zealand

MedicalResearch.com: What are the main findings of the study?

Prof. Bolland: In a meta-analysis of 20 randomized clinical trials, there was no effect of vitamin D with or without calcium on falls.  In a trial sequential analysis of these trials, the effect estimate for vitamin D with or without calcium on falls lay within the futility boundary, providing reliable evidence that vitamin D supplementation does not alter the relative risk of falls by ≥15% and suggesting that future trials that are similar in design to current trials are unlikely to change that conclusion.

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Severe Obesity Linked to Vitamin D Deficiency

MedicalResearch.com Interview with:
Tomás Ahern MB, BCh, BAO
St Columcille’s Hospital and St Vincent’s University Hospital
Dublin, Ireland

MedicalResearch.com: What are the main findings of the study?

Answer: More than 40% of severely obese people, who make up 6.5% of American adults, are at risk of vitamin D deficiency.

Severely obese people with low vitamin D levels are less active and have worse physical function than those with healthy vitamin D levels. Other investigators have found that poor physical function predicts premature death – whether this is the case in people with severe obesity remains to be determined.

MedicalResearch.com: Were any of the findings unexpected?

Answer: Yes. Other studies, of people without severe obesity, have shown that people with low vitamin D levels have higher blood sugar levels and are more likely to have diabetes. We did not find such a relationship in this study of people with severe obesity.

MedicalResearch.com: What should clinicians and patients take away from your report?

Answer: Determining serum 25-hydroxyvitamin D levels in severely obese people is appropriate because low levels are common and associated with poor physical activity and poor physical function.

The finding of a low 25-hydroxyvitamin D level should be a portal to interventions that improve physical function and should lead to consideration of vitamin D supplementation. Vitamin D supplementation can take the form of spending more time outdoors or chewing calcium and vitamin D tablets daily.

MedicalResearch.com: What recommendations do you have for future research as a result of this study?

Dr. Ahern: We feel that this study generates the imperative to determine the effects of vitamin D supplementation in severely obese people at risk of vitamin D deficiency. We feel it likely that vitamin D supplementation in this group will result in improvement in physical function and possibly improvement in other markers of increased mortality.

Citation:

Association between Vitamin D Status and Physical Function in the Severely Obese

T. Ahern, A. Khattak, E. O’Malley, C. Dunlevy, M. Kilbane, C. Woods, M. J. McKenna, D. O’Shea. Association Between Vitamin D Status and Physical Function in the Severely Obese. The Journal of Clinical Endocrinology & Metabolism, 2014; jc.2014-1704 DOI: 10.1210/jc.2014-1704

 

Vitamin D: Evidence for Widespread Supplementation Weak

Evropi Theodoratou School of Molecular, Genetic and Population Health Sciences University of EdinburghMedicalResearch.com Interview with:
Evropi Theodoratou
School of Molecular, Genetic and Population Health Sciences
University of Edinburgh

MedicalResearch.com: What are the main findings of the study?

Answer: We identified 268 studies either meta-analyses or systematic reviews of plasma vitamin D concentrations or meta-analyses of randomised trials of vitamin D supplementation.

The relation between vitamin D and 137 outcomes has been explored, covering a wide range of skeletal, malignant, cardiovascular, autoimmune, infectious, metabolic, and other diseases.

Ten outcomes were examined by both meta-analyses of observational studies and meta-analyses of randomised trials, but the direction of the effect and level of statistical significance was concordant only for birth weight.

Despite a few hundred systematic reviews and meta-analyses, highly convincing evidence of a clear role of vitamin D does not exist for any outcome, but associations with a selection of outcomes are probable: birth weight, dental caries in children, maternal vitamin D concentrations at term, and parathyroid hormone concentrations in chronic kidney disease patients requiring dialysis.

Finally, despite the vast volume of published studies, this review highlights the absence of meta-analyses in relation to autoimmune disease (either of observational studies or randomised clinical trials), and the absence of meta-analyses of randomised clinical trials of vitamin D supplementation in respect to cancer, cognitive and infectious disease outcomes.

MedicalResearch.com: Were any of the findings unexpected?

Answer: In contrast to previous reports, evidence does not support the notion that vitamin D only supplementation increases bone mineral density or reduces the risk of fractures or falls in older people.

MedicalResearch.com: What should clinicians and patients take away from your report?

Answer: The lack of convincing associations and the relative dearth of probable associations suggest that evidence for benefits that may be reaped from population-wide vitamin D supplementation is weak at least for supplementation levels considered by studies included in this review.

Probable associations, for which highly significant effects appear in randomised trials, hold the most promise for clinical translation, but they pertain to specific populations (children, pregnant women, patients with chronic kidney disease).

MedicalResearch.com: What recommendations do you have for future research as a result of this study?

Answer: As universal conclusions about vitamin D benefits cannot be drawn, further studies and better designed trials (in relation to dose and vitamin D only supplementation) especially for cancer and autoimmune related outcomes are needed.

Citation:

Calcium-Vitamin D Supplementation: Effects on Vitamin D and Cholesterol Levels

Peter F. Schnatz, D.O. Associate Chair & Residency Program Director The Reading Hospital Department of OB/GYN Reading, PA  19612-6052MedicalResearch.com Interview with:
Peter F. Schnatz, D.O.
Associate Chair & Residency Program Director
The Reading Hospital
Department of OB/GYN
Reading, PA  19612-6052

MedicalResearch.com: What are the main findings of the study?

Dr. Schnatz: In a subsample of 576 women from the parent WHI CaD (calcium plus vitamin D supplementation)  trial* , there was a significant (38%) increase in mean serum 25OHD3 concentrations after two years (95% CI 1.29-1.47, p< 0.001) for women randomized to CaD (24.3ng/mL vs. 18.2 ng/mL).

Women randomized to CaD had a 4.5 mg/dL mean decrease in LDL-C which was statistically significant.  After accounting for serum 25OHD3 concentration, the effect of CaD was attenuated, suggesting that higher concentrations of 25OHD3, in response to CaD supplementation, are associated with improved LDL-C.

In observational analyses, higher concentrations of 25OHD3 were associated with significantly higher HDL-C along with significantly lower LDL-C and TG concentrations.

* 1,000 mg of elemental calcium plus 400 IU of vitamin D3 daily
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Pre-Op Vitamin D and Infection Risk Following Gastric Bypass Surgery

Sadeq A. Quraishi, MD, MHA Massachusetts General Hospital, Harvard Medical School Boston, MassachusettsMedicalResearch.com Interview with:
Sadeq A. Quraishi, MD, MHA
Massachusetts General Hospital, Harvard Medical School
Boston, Massachusetts


MedicalResearch.com: What are the main findings of the study?

Dr. Quraishi: Our retrospective study suggests that there is an association between pre-operative 25-hydroxyvitamin D [25(OH)D] levels and the risk of hospital-acquired infections after gastric bypass surgery. In particular, patients with 25(OH)D levels <30 ng/ml before surgery were almost 4 times more likely to develop a surgical site infection within 30 days of surgery than patients with pre-operative 25(OH)D levels at 30 ng/ml or higher.

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