Category Archives: Vitamin D

Vitamin D and Colorectal Cancer Risk – What is the Correlation?

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MedicalResearch.com Interview with:

Stephanie J. Weinstein, M.S., Ph.D.  Metabolic Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH 

Dr. Weinstein

Stephanie J. Weinstein, M.S., Ph.D. 
Metabolic Epidemiology Branch, Division of Cancer Epidemiology and Genetics
National Cancer Institute, NIH  

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

Response: Vitamin D, known for its role in maintaining bone health, is hypothesized to lower colorectal cancer risk via several pathways related to cell growth and regulation. Previous prospective studies have reported inconsistent results for whether higher concentrations of circulating 25-hydroxyvitamin D, the accepted measure of vitamin D status, are linked to lower risk of colorectal cancer. The few randomized clinical trials of vitamin D supplementation and colorectal cancer completed thus far have not shown an effect; but study size, relatively short supplementation duration, and only moderate compliance may have contributed to their null findings.

To address inconsistencies in prior studies on vitamin D, and to investigate associations in population subgroups, we harmonized and analyzed participant-level data from over 5,700 colorectal cancer cases who had blood collected before colorectal cancer diagnosis, and 7,100 matched cancer-free controls. Study participants were drawn from 17 prospective cohorts from the United States, Europe, and Asia and were followed for an average of 5.5 years (range: 1 – 25 years). We used a single, widely accepted assay and laboratory for new vitamin D measurements and calibrated existing vitamin D measurements. In the past, substantial differences between assays made it difficult to integrate vitamin D data from different studies. Our novel calibration approach enabled us to explore risk systematically over the broad range of vitamin D levels seen internationally.  Continue reading →

Higher Vitamin D Levels Linked to Lower Breast Cancer Incidence

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MedicalResearch.com Interview with:

Cedric F. Garland, Dr.P.H., F.A.C.E. Adjunct Professor Division of Epidemiology Department of Family Medicine and Public Health University of California San Diego La Jolla, California 92093-0620

Dr. Garland

Cedric F. Garland, Dr.P.H., F.A.C.E.
Adjunct Professor
Division of Epidemiology
Department of Family Medicine and Public Health
University of California San Diego
La Jolla, California 92093-0620

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

Response: Studies mapping death rates from female breast cancer in the US, the former USSR and Canada by Drs. Edward Gorham, and Frank and Cedric Garland revealed for the first time in history that death rates from breast cancer tracked latitude where people lived.

The rates were highest in the least sunny northern tier of states, lowest in the sunny southwest. This led these scientists to be the first to theorize that vitamin D prevents breast cancer” said study first author Sharon McDonnell. Continue reading →

Severely Malnourished Children May Benefit From Vitamin D Supplement

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MedicalResearch.com Interview with:
Dr Javeria Saleem PhD
Department of Public Health, Institute of Social and Cultural Studies, University of the Punjab, Lahore, Pakistan
Centre for Primary Care and Public Health, Blizard Institute, Barts and The London School of Medicine and Dentistry
Queen Mary University of London
London, United Kingdom

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

Response: Severe acute malnutrition is the most extreme and visible form of undernutrition. Affected children have very low weight for their height and severe muscle wasting; they may also have swollen feet, face and limbs. Around 20 million children suffer from severe acute malnutrition worldwide of whom an estimated 1.4 million live in Pakistan. The condition is a major cause of death in children under 5 in Asia and Africa. The standard treatment is to give a high-energy, micronutrient enhanced paste called ready-to-use therapeutic food (RUTF).

Vitamin D deficiency has been reported to be a risk factor for severe wasting in children with severe acute malnutrition Ready-to-use therapeutic food contains relatively modest amounts of vitamin D. However, the effects of adding high-dose vitamin D to this standard treatment have not previously been evaluated.

We therefore did a clinical trial to assess whether high-dose vitamin D hastened recovery in 185 children aged 6-58 months who were receiving standard treatment for severe acute malnutrition in Southern Punjab, Pakistan. The 93 children in the active arm of the study received two doses of 5 mg vitamin D by mouth, while the 92 children in the control arm received placebo (a dummy medicine containing no vitamin D).

Our findings were very striking: after 2 months of treatment, the children who received high-dose vitamin D in addition to standard therapy had significantly better weight gain, and significantly better motor and language development, than those who received standard treatment alone.

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How To Prevent the Elderly From Falling?

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MedicalResearch.com Interview with:

Dr. Alex Krist

Dr. Krist

Dr. Alex Krist, M.D., M.P.H.

Dr. Krist is is a professor of family medicine and population health at Virginia Commonwealth University and active clinician and teacher at the Fairfax Family Practice residency.

What is the background for these recommendation statements? What are the main findings?

Response: Falls are the leading cause of injuries in adults age 65 and older and can lead to serious disability and even death. Bone fractures—which may result from a fall—can also cause serious disability and death in older adults.

The U.S. Preventive Services Task Force looked into the most recent evidence on the best ways to prevent falls and fractures in older adults. We found that clinicians should recommend exercise or physical therapy to help prevent falls by older adults who live at home and are at higher risk for falling.

Additionally, we concluded that taking a low dose of vitamin D and calcium does not help prevent fractures due to osteoporosis, but we don’t know if taking a higher dose is effective or not, so we are calling for more research.

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Older, Frail and Physically Inactive Adults At Risk of Multivitamin Deficiency

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MedicalResearch.com Interview with:
“vitamins” by Colin Mutchler is licensed under CC BY 2.0Priv.-Doz. Dr. Barbara Thorand 
Helmholtz Zentrum München
German Research Center for Environmental Health
Institute of Epidemiology II
Neuherberg, Germany 

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

Response: Micronutrients, which include vitamins, minerals (e.g. calcium) and trace elements (e.g. iron), are essential nutrients that are required in minute amounts by the organism for proper growth and good health. Results from the last German National Nutrition Survey (NVS II)* uncovered a high prevalence of insufficient dietary intake of micronutrients in older adults aged 65 years and over in Germany. By means of blood analyses, our study has confirmed these critical results. This is a highly relevant issue, particularly in light of our growing aging population and the high societal relevance of successful healthy aging.

*Max Rubner-Institut: Nationale Verzehrsstudie II, Ergebnisbericht Teil 2 (2008). Die Bundesweite Befragung zur Ernährung von Jugendlichen und Erwachsenen.

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

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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

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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

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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

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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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Vitamin D Deficiency Highly Prevalent in Pediatric Irritable Bowel Syndrome

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MedicalResearch.com Interview with:

Benjamin Udoka Nwosu, MD, FAAP Associate Professor of Pediatrics Division of Endocrinology University of Massachusetts Medical School Worcester, Massachusetts

Dr. Nwosu

Benjamin Udoka Nwosu, MD, FAAP
Associate Professor of Pediatrics
Division of Endocrinology
University of Massachusetts Medical School
Worcester, Massachusetts

MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Vitamin D deficiency has been reported in various gastrointestinal disorders but the vitamin D status of children and adolescents with irritable bowel syndrome (IBS) has not been previously characterized.

Secondly, the vitamin D status in IBS has not been compared to those of other malabsorption syndromes such as irritable bowel syndrome, lactose intolerance, and celiac disease.

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

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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

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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

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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

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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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Screening Tears, Not Blood, For Vitamin Deficiencies

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MedicalResearch.com Interview with:

Adrienne R. Minerick, Ph.D. Associate Dean for Research & Innovation, College of Engineering Assistant to the Provost for Faculty Development Professor, Chemical Engineering Michigan Technological University Houghton, MI 49931

Dr. Adrienne Minerick

Adrienne R. Minerick, Ph.D.
Associate Dean for Research & Innovation, College of Engineering
Assistant to the Provost for Faculty Development
Professor, Chemical Engineering
Michigan Technological University
Houghton, MI 49931

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

Response: With seed funding from the Gerber Foundation, we asked two scientific questions.
1. Are vitamins present in tears and could we reliably detect them?
2. Do the vitamin levels in tears correlate with the vitamin levels in blood?

This research, conducted by recent PhD graduate Maryam Khaksari, illustrated that vitamins are present in tears. The majority of the essential vitamins are water soluble, which were present in tears in higher concentration than fat soluble vitamins. Given that tears are 98% water, this result wasn’t surprising. This study developed up protocols to reliably detect both water and fat soluble vitamins. The limits of detection and limits of quantification did vary by vitamin, so there is ample room to improve this technique.
The second question was answered by a small clinical trial with UP Health: Portage Hospital’s Pediatric Clinic. During the 4-month well-baby check-up, willing parents and their infant each donated both a blood sample and a tear sample. Vitamin concentrations were determined in the samples and correlations quantified. Fat soluble vitamin K showed the strongest concentration correlation between blood and tears. The strength of additional vitamin correlations were noted. These early-stage results demonstrate that vitamin screening from a single drop of tears (35uL or microliters) is feasible – with additional refinement.

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Low Vitamin D Linked To Increased Risk of Chronic Headache

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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

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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?

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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

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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

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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

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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

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

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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

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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

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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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