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Abuse and Neglect, Aging, Weight Research / 21.06.2015

MedicalResearch.com Interview with: Dr. Min Du Ph.D Department of Animal Sciences Washington Center for Muscle Biology Washington State University Pullman, WA Medical Research: What is the background for this study? What are the main findings? Response: The beige fat is only recently identified and is highly inducible. we observed that polyphenolic compounds including resveratrol enhances AMPK activity, and hypothesized that resveratrol might enhance the formation of beige fat through activation of AMPK. Therefore, we used resveratrol, a very well characterized polyphenolic compound as a representative of polyphenolic compounds in fruits, to check its effects on the formation of beige fat. We found that resveratrol induced the formation of beige adipocytes both in vitro and in vivo. We further found that the lipid oxidation rate was enhanced due to the formation of beige fat, which is correlated with the anti-obesity effect of resveratrol. (more…)
Author Interviews, OBGYNE, Weight Research / 12.06.2015

MedicalResearch.com Interview with: Theresa A Lawrie World Health Organization Department of Reproductive Health and Research Geneva, Switzerland MedicalResearch: What is the background for this study? Response: Excessive weight gain in pregnancy is associated with various undesirable outcomes in pregnancy. The aim of the review was to assess data from all relevant clinical trials in the field, to determine whether diet and/or exercise interventions during pregnancy were effective in reducing the chance of excessive weight gain in pregnancy. We also wanted to know whether these interventions could reduce the chance of having large babies (macrosomia), as this is associated with difficult labor, c/section, postpartum hemorrhage, birth injuries and other complications. MedicalResearch: What are the main findings? Response: Altogether 49 trials contributed data to the review. Approximately half the trials recruited women of any pre-pregnancy weight, the other half recruited women who were overweight or obese at the start of pregnancy. Most of the trials were conducted in high income countries. Interventions varied, some involved individual counseling, others group sessions, some were counseling interventions only, other programs were actively supervised by fitness trainers. Health outcomes for women receiving the intervention programs in addition to routine antenatal care (the intervention group) were compared with those of women receiving the routine antenatal care only (the control group). We found that diet or exercise or combined interventions led to an average 20% reduction in the number of women gaining excessive weight in pregnancy. This reduction was fairly consistent across the different types of interventions, although the largest effect was observed for combined diet and supervised exercise interventions. Overall findings suggested a small reduction in caesarean section (of about 5%) and in large babies (of about 7%).  However, a bigger reduction in large babies (in the region of a 19% reduction) was noted for exercise-only interventions, which were more likely to be supervised interventions. Other findings: We also found no difference in the risk of preterm birth between groups. Fewer women in the intervention group were assessed as having high blood pressure during pregnancy (although we assessed this as low quality evidence). Low quality evidence also suggested that women in the intervention group were likely to retain less weight at six months postpartum compared with the control group. Interestingly, data from two studies suggested that women receiving diet and exercise interventions were less likely to have babies with breathing difficulties at birth. These findings will hopefully be corroborated by other studies. A limitation of the review, is that we did not include gestational diabetes as an outcome as this is partly covered in a separate Cochrane review. Our exploratory analyses, however, suggested that there may be a reduction in gestational diabetes for certain types of interventions, and we hope to include these data in future review updates. In general, we did not find differences in outcomes for women according to pre-pregnancy weight or BMI. (more…)
Author Interviews, Heart Disease, JACC, Weight Research / 31.05.2015

MedicalResearch.com Interview with: Christopher X Wong MBBS MSc PhD Clinical Research Fellow | Clinical Trial Service Unit, Oxford Clinical Senior Lecturer | Centre for Heart Rhythm Disorders, Adelaide Clinical Trial Service Unit, University of Oxford Roosevelt Drive, Oxford Medical Research: What is the background for this study? What are the main findings? Dr. Wong: Atrial fibrillation is an increasingly common heart rhythm disorder. This study demonstrates that even small increments in obesity are associated with a significantly increased risk of atrial fibrillation. Our data suggest that for every 1 unit reduction in body mass index there may be a 3-5% reduction in atrial fibrillation; for every 5 unit reduction, there may be 10-29% reductions. It should also be noted that this is likely to be a significant underestimate of the effect of weight reduction on atrial fibrillation rates as weight control has favourable effects on other risk factors for atrial fibrillation, such as hypertension and diabetes. Given the more than 45 million people with atrial fibrillation worldwide, even small but widespread reductions in obesity would thus help contain this ‘epidemic’ of atrial fibrillation. (more…)
Author Interviews, Diabetes, Genetic Research, Weight Research / 22.05.2015

MedicalResearch.com interview Dorota Kaminska, MSc Department of Clinical Nutrition University of Eastern Finland MedicalResearch: What is the background for this study? What are the main findings? Response: The prevalence of obesity is increasing worldwide, making it one of the biggest health problems currently facing both developed and developing countries. Obesity is considered a primary risk factor for developing type 2 diabetes. While the majority of people with type 2 diabetes are obese, most of obese people do not develop diabetes, indicating that obesity is not the only risk factor for type 2 diabetes. Both obesity and type 2 diabetes are multifactorial complex diseases that are caused by a combination of genetic, environmental, and lifestyle factors. Results from twin studies suggest that genetic factors explain 50% to 90% of the variance in body mass index (BMI) and from 45% to 85% of the diabetes risk. However genetic variations identified by genome wide association studies (GWAS) explain only 2-4% of the obesity risk and 5-10% of the type 2 diabetes risk. Several options have been debated to be a source of so called “missing heritability”, including, among others, structural DNA variations, gene-gene and gene-environment interactions, epigenetic modifications and RNA splicing. We used adipose tissue samples from Kuopio Obesity Surgery (KOBS), very low calorie diet (VLCD), Metabolic Syndrome in Men (METSIM) and European Network on Functional Genomics of Type 2 Diabetes (EUGENE2) studies to determine alternative splicing pattern of selected genes. The study focused on determining the effects of obesity and weight loss on alternative splicing of metabolically active genes (TCF7L2 and INSR). We showed that alternative splicing of both genes is dysregulated in obesity and type 2 diabetes, resulting in impaired insulin action in adipose tissue. Additionally we demonstrated, that obesity induced changes in splicing can be reversed by weight loss induced by gastric bypass surgery or very low calorie diet. Furthermore, the study identified alternatively spliced genes in the genomic regions associated with obesity risk, demonstrating that splicing of the MSH5 gene in subcutaneous fat is regulated by weight loss. The study also found that body mass index is a main determinant of TRA2B, BAG6 and MSH5 splicing in subcutaneous fat; however, the functional consequences of this finding require further investigation. These findings imply that the obesity-associated gene variants might act through regulation of splicing which in turn might underlie the pathogenesis of obesity in individuals carrying the risk variants. (more…)
AHA Journals, Author Interviews, Heart Disease, Metabolic Syndrome, Race/Ethnic Diversity, Weight Research / 21.05.2015

Michelle Schmiegelow, MD, PhD-studerende Hjertemedicinsk Forskning Gentofte Universitetshospital HellerupMedicalResearch.com Interview with: Michelle Schmiegelow, MD, PhD-student Hjertemedicinsk Forskning Gentofte Universitetshospital Hellerup Medical Research: What is the background for this study? Dr. Schmiegelow:  Obesity has become a worldwide epidemic, but the excess cardiovascular risk observed in obese individuals may primarily be attributable to metabolic mediators, rather than obesity per se. Several studies conducted in primarily non-Hispanic white populations suggest that obese individuals without the metabolic syndrome, defined as metabolically healthy obese, have a cardiovascular risk similar to that of normal weight metabolically healthy individuals. We used prospectively collected data from the Women’s Health Initiative studies to evaluate whether obesity unaccompanied by metabolic abnormalities was associated with increased risk of cardiovascular disease (CVD) across racial/ethnic subgroups in postmenopausal women. Additionally, we examined whether the use of the metabolic syndrome to define the metabolically healthy obese applied to the various racial/ethnic subgroups by quantifying the number and type of metabolic syndrome components. All women were classified by obesity level and metabolic health status at baseline. The women were thus categorized according to body mass index (BMI, kg/m2) into normal weight (BMI 18.5-24.9 kg/m2), overweight (25-29.9 kg/m2) and obese (30.0 kg/m2) women. Metabolic health status was first defined by presence of the metabolic syndrome (yes/no), and second by number of metabolic syndrome components. In accordance with the International Diabetes Federation and the American Heart Association/National Heart, Lung, and Blood Institute we defined the metabolic syndrome as any two of the following (criteria for women): increased waist circumference ≥80 cm; increased level of triglycerides ≥150 mg/dL (≥1.7 mM); decreased level of HDL-C <50 mg/dL (<1.3 mM); increased blood pressure with either systolic blood pressure ≥130 mmHg or diastolic blood pressure ≥85 mmHg, or treatment with antihypertensive drugs; and impaired fasting serum glucose ≥100 mg/dL (6.1 mM). Medical Research: What are the main findings? Dr. Schmiegelow: The study population comprised 14,364 women without diabetes or prior cardiovascular disease. The women had a median age of 64 years (interquartile range 57–69), and 47% were white, 36% were black and 18% were Hispanic. Over a median follow-up of 13 years (interquartile range 12–14 years), 1,101 women (7.7%) had a first cardiovascular event. The main findings of this study were that metabolic abnormalities appeared to confer more cardiovascular risk among black women than among white women. Consistent with other studies, among white women without the metabolic syndrome, obesity was not associated with increased cardiovascular risk compared with normal weight women. Conversely, black overweight and black obese women had increased cardiovascular risk compared with normal weight black women without the metabolic syndrome, even in absence of the metabolic syndrome. According to number of metabolic syndrome components, black overweight or obese women with just two metabolic abnormalities had increased risk of cardiovascular disease, although they would be considered “metabolically healthy” based on the standard definition, particularly since one of these abnormalities were abdominal obesity for 79% of overweight and 98% of obese women, irrespective of race/ethnicity. White obese women with three metabolic abnormalities did not have a statistically significantly increased cardiovascular risk compared with normal weight metabolically healthy women. Thus, cardiovascular disease risk appeared to be elevated in black women by the presence of only two or three metabolic abnormalities to a degree that would require four or more metabolic abnormalities among white women. These findings did not appear to be driven by any particular combination of metabolic abnormalities. (more…)
Author Interviews, Weight Research / 12.05.2015

MedicalResearch.com Interview with: Dr Margaret Ashwell OBE, FAfN, RNutr (Public Health) Ashwell Associates Ashwell, Hertfordshire, United Kingdom. Visiting Research Fellow, Oxford Brookes University

MedicalResearch: What are the main findings from this study?

Dr. Ashwell: In this study, the authors explore the differences in CVD risk factors between overweight and non-overweight people (by BMI) according to their shape (waist-to-height ratio -WHtR) Data for their analysis was taken from the Health Survey for England 2009 (HSE). They found significant differences in levels of total cholesterol (TC) and glycat­ed haemoglobin (HbA1c—a measure of blood sugar control used to diagnose diabetes). Out of 2917 people aged 16 years and over, 346 classified as ‘normal’ by BMI, have WHtR exceeding 0.5 (12% of the total,sample, or 34% of normal weight people). These could be called non-overweight ‘apples’, who have a lot of fat around the waist but not a high BMI. The researchers classified the HSE population into four groups (2×2) using standard boundary values of BMI (above or below 25kg/m2) and WHtR (above or below 0.5). The group with ‘low/normal BMI but high WHtR (non-overweight ‘ap­ples’) had significantly higher mean TC than the group with high BMI but low WHtR (overweight ‘pears’—people with a higher than normal BMI but less fat around the waist): 5.73mmol/L vs. 4.98mmol/L. Similarly, HbA1c levels were higher among non-over­weight ‘apples’ than among overweight ‘pears’ (5.62% vs. 5.33%). These differences were similar and also significant in both sexes.

MedicalResearch: Why do you say that piece so string can be used for primary screening?

Dr. Ashwell: Since a good boundary value for waist-to-height ratio is 0.5, you don't even need a tape measure to screen those at risk. It can be done with a piece of string. Measure the height of child with string, fold it in half and see if it fits around his/her waist.   If it doesn't, that child should proceed to the next stage of screening. (more…)
Author Interviews, Pediatrics, Weight Research / 12.05.2015

Matthew PearceMedicalResearch.com Interview with: Matthew Pearce NHS Gloucestershire Clinical Commissioning Group UK Medical Research: What is the background for this study? What are the main findings? Response: Despite evidence to suggest that the prevalence of childhood obesity in the UK has stabilized in recent years, we know that approximately one in five children start their school life either overweight or obese, increasing to one in three children by the last year in primary school. Our research was the first to undertake an in-depth analysis on the UK’s National Child Measurement Programme (NCMP) and retrospectively track the weights of individual children over a 7-year period. Our study included a sample of 1863 children in South Gloucestershire, Bristol in the UK. Our results were found to be similar to cross sectional data with obesity prevalence approximately doubling between the first (4/5yrs old) and last year (10/11yrs old) of primary school. Our findings provide little reassurance that those children who are obese in early childhood ‘grow out of ’ excess adiposity. Including overweight, we found that 84% of obese children at Reception year went on to be either overweight or obese by Year 6. Although previous studies have failed to identify any significant differences in BMI change between boys and girls during mid-childhood, our research found that more boys than girls dropped a weight category (from overweight or obese) by the time they reached Year 6. We found that the odds ratios of being overweight (BMI ?85th percentile) or obese (?95th percentile) based on BMI at Reception were similar to published literature. Our data found children who are within the upper range of the healthy weight category (75th–85th percentile) at Reception had an increased risk of being overweight or obese by the time they reach year 6. (more…)
Author Interviews, Nutrition, Sugar, Weight Research / 08.05.2015

Dr. Dragos Petrescu Department of Public Health and Primary Care CambridgeMedicalResearch.com Interview with: Dr. Dragos Petrescu Department of Public Health and Primary Care Cambridge Medical Research: What is the background for this study? What are the main findings? Response: Consumption of sugar-sweetened beverages is a major contributor to obesity, particularly in children. Recent systematic reviews provide good evidence that reducing portion size reduces consumption. Similarly, evidence suggests that container shapes and product placement in supermarkets can influence consumption. The public acceptability of "nudging" -- altering properties such as the size, the shape, and location of sugar-sweetened beverages -- to improve public health is unknown. Here we compared the acceptability in UK and USA samples of government interventions to reduce consumption of sugar-sweetened beverages: three nudge interventions (limiting portion size, changing container shape, and changing shelf location) and two traditional interventions (increased taxation and an education campaign). We found that for the majority of UK and USA samples, the education campaign and the three nudge interventions were acceptable, with education attracting most support.  By contrast, only a minority of participants supported taxation. (more…)
Accidents & Violence, Author Interviews, Weight Research / 08.05.2015

MedicalResearch.com Interview with: Claudia Sikorski Dr. rer. med. Claudia Sikorski, Dipl.-Psych. Institut für Sozialmedizin, Arbeitsmedizin und Public Health (ISAP) Institute of Social Medicine, Occupational Health and Public Health Universität Leipzig, Medizinische Fakultät Leipzig Medical Research: What is the background for this study? What are the main findings? Response: Obesity is a highly stigmatized condition. People with obesity are often regarded a lazy, slow and sloppy. One consequence of these negative attitudes may be discrimination, e.g. the unfair treatment of individuals with obesity. This study, conducted by Jenny Spahlholz, myself and colleagues reviews observational and experimental studies that investigated the occurrence and nature of discrimination in obesity. (more…)
Author Interviews, Weight Research / 08.05.2015

MedicalResearch.com Interview with: Rebecca Jones, MSPH Nutrition and Health Sciences Program Graduate Division of Biological and Biomedical Sciences Emory University Medical Research: What is the background for this study? What are the main findings? Response: Obesity in children is associated with a wide range of conditions later in life including heart disease, cancer, and diabetes. Even prior to adulthood, children can be affected by a host of non-communicable diseases which are affected by weight status of the child. With an increase in children who are overweight or obese globally, Dr. Chan, Director-General of the World Health Organization, announced a new initiative to combat childhood obesity at the 2014 World Health Assembly. Within childhood obesity the pre-school (under age 5) years are a critical period for prevention due the association of adiposity rebound and obesity in later years as well as the early establishment of taste preferences and attitudes around healthy eating habits. Recent evaluation of incident obesity in the United States has demonstrated a component of the course to obesity is already established by the age of five years. Our main finding is the necessity for better surveillance and comparability of weight status, particularly overweight and obesity, in children under five across countries in the European region. 60% of countries within the region have some form of published data on this particular population however they vary based on level of national representation, cut-off criteria, age and gender. All these different factors can significantly change the prevalence estimates making it very difficult to ascertain the full nature of the problem. Based on the data which was available the European Region has reason for concern about overweight and obesity in young children. (more…)
Author Interviews, Diabetes, General Medicine, Statins, UT Southwestern / 08.05.2015

Ishak Mansi, MD Staff Internist, VA North Texas Health System. Professor in Department of Medicine & Department of Clinical Sciences, Division of Outcomes and Health services Research, University of Texas Southwestern, Dallas, TXMedicalResearch.com Interview with: Ishak Mansi, MD Staff Internist, VA North Texas Health System. Professor in Department of Medicine & Department of Clinical Sciences, Division of Outcomes and Health services Research, University of Texas Southwestern, Dallas, TX MedicalResearch: What is the background for this study? What are the main findings? Dr. Mansi:  Statin use is associated with increased incidence of diabetes, and possibly increased body weight, and less exercise capacity. Data on the long-term effects of these associations in healthy adults are very limited. Additionally, the effects of these associations on diabetic complications have not been adequately studied. Dr. Mansi at VA North Texas Health System, Dallas and Professor of Medicine and Clinical Sciences at the University of Texas Southwestern, Dallas, TX and his colleagues found that among generally healthy individuals, statin-users in comparison to non-users had a higher odds of being diagnosed with new onset diabetes, diabetes with complications, and overweight/obesity. The researchers examined the records of tens of thousands of Tricare beneficiaries, during the period from 10/1/2003 to 3/1/2012. After excluding patients who had at baseline a preexisting cardiovascular diseases or severe chronic diseases that may be life-limiting (including diabetes mellitus), they identified a cohort of 25,970 patients as “healthy cohort”. They, further, matched 3,351 statins-users and 3,351 nonusers on several baseline characteristics to ensure comparability. There are 3 main important findings for our study:
  1. Statin use was associated with significantly higher risk of new onset diabetes even in a very healthy population. Whereas the risk of diabetes with statins is known, it was thought that this may be due to the overall multiple risks of statin-users (that caused them to receive statins as a therapy).
  2. Statin use was associated with very high risk of diabetes complications in this healthy population: this was never shown before.
  3. Statin use is associated with higher risk of obesity: this also is widely unknown. However, few studies have noted this (one study using patient survey noted this, another study using Mendelian randomization showed it, and post-hoc analysis of a clinical trial showed that statin user gained more weight). Our study, which used a different methodology (retrospective cohort study) add another piece of evidence. Obesity is at endemic level in the US and treatment options are limited.
High-intensity statins was associated with greater risks of all outcomes. This article is published in the Journal of General Internal Medicine (JGIM). JGIM is the official journal of the Society of General Internal Medicine. (more…)
Author Interviews, Pediatrics, UCSD, Weight Research / 28.04.2015

Mark D. DeBoer, MD, MSc, MCR Associate Professor of Pediatrics Division of Pediatric Endocrinology, University of VirMedicalResearch.com Interview with: Mark D. DeBoer, MD, MSc, MCR Associate Professor of Pediatrics Division of Pediatric Endocrinology, University of Virginia Medical Research: What is the background for this study? What are the main findings? Dr. DeBoer: The American Academy of Pediatrics recommends that children watch no more than 2 hours of TV daily. We wanted to see if children watching shorter amounts of TV were more likely to have higher weight status. We found that children in kindergarten who watched 1-2 hours a day were more than 40% more likely to be overweight and obese and gained more unhealthy weight over the next year. (more…)
Author Interviews, Microbiome, Pediatrics, Weight Research / 10.04.2015

MedicalResearch.com Interview with: Lisa J. Martin PhD Professor Division of Human Genetics Jessica G. Woo PhD Associate Professor Division of Biostatistics and Epidemiology Cincinnati Children’s Hospital Medical Center Cincinnati, OH MedicalResearch: What is the background for this study? Response: Obesity is a major public health concern. In the past 30 years, more and more children are being considered obese. Because treatment is challenging, researchers are looking toward prevention. The health benefits of breastfeeding over infant formula feeding are well recognized, including evidence that breastfeeding may protect against obesity. But, how much protection it provides and the reasons for protection are unclear. Thus, the purpose of this paper was to examine the relationship between breastfeeding and reduced risk of obesity later in life, with special emphasis on potential mechanisms. MedicalResearch: What are the main findings? Response: After reviewing more than 80 studies conducted over a period of 20 years, the authors showed that breastfeeding is associated with a 10 to 20 percent reduction in obesity prevalence in childhood. Mechanisms that connect human milk and infant physiology include maternal obesity, development of a healthy gut environment (microbiome) in the infant, and the development of taste preference and diet quality. Importantly, each of these mechanisms can be influenced by biologic and social factors which may directly and indirectly affect the child’s obesity risk. (more…)
Author Interviews, Diabetes, Stem Cells, Weight Research / 25.03.2015

Timothy J. Kieffer Ph.D. | Professor Laboratory of Molecular & Cellular Medicine Department of Cellular & Physiological Sciences Department of Surgery | Life Sciences Institute The University of British Columbia Vancouver BC Canada MedicalResearch.com Interview with: Timothy J. Kieffer Ph.D. | Professor Laboratory of Molecular & Cellular Medicine Department of Cellular & Physiological Sciences Department of Surgery | Life Sciences Institute The University of British Columbia Vancouver BC Canada Medical Research: What is the background for this study? What are the main findings? Dr. Kieffer: Previously we have examined the therapeutic potential of pancreatic precursor cells derived from human stem cells for insulin replacement in models of type 1 diabetes (PMID: 22740171 & PMID: 23771205). Here we sought to test the efficacy of cell-based insulin replacement in a model of type 2 diabetes, which is by far the most common form of diabetes. Key aspects of type 2 diabetes could be mimicked in immunodeficient mice, namely hyperglycemia and insulin resistance accompanied by excess body weight, by placing the mice on high fat diets. These diabetic mice were transplanted with human stem cell derived pancreatic precursor cells contained within macroencapsulation devices. The diabetic setting did not negatively impact the ability of the transplanted cells to mature into insulin-producing cells. Moreover, the cell transplants were able to significantly improve glucose homeostasis, particularly when combined with low doses of traditional anti-diabetic drugs. Intriguingly, the combined therapy also induced weight loss, such that treated mice were similar in weight to control mice reared on a low fat diet. (more…)
Author Interviews, Heart Disease, Weight Research / 24.03.2015

Abhishek Sharma MD (on behalf of all co-authors) Division of Cardiovascular Medicine State University of New York Downstate Medical Center Brooklyn, New YorkMedicalResearch.com Interview with: Abhishek Sharma MD (on behalf of all co-authors) Division of Cardiovascular Medicine State University of New York Downstate Medical Center Brooklyn, New York MedicalResearch: What is the background for this study? Authors: Heart failure (HF) is the second most common cause of hospitalization after child delivery in the US. In general, increasing degrees of obesity have been associated with progressively worse outcomes among individuals without known cardiovascular (CV) diseases. Therefore intentional weight loss, via structured dietary and exercise training programs or bariatric surgery, has been suggested to reverse hemodynamic and cardiac structural changes associated with obesity. However, several recent studies have reported lower mortality and morbidity among heart failure patients who were overweight or obese compared with those whose weight was normal or subnormal. This phenomenon has been commonly labeled the “obesity paradox” or “reverse epidemiology.” These findings question the prognostic significance of BMI and the practice of extrapolating findings derived from the general population to HF patients. Reasons for the association between BMI and all- cause and CV mortality and hospitalizations in HF are not fully understood. Due to contradictory results in various studies and lack of definitive data on prognostic value of BMI and its purposeful alteration in HF, the American College of Cardiology Foundation/American Heart Association do not provide any firm recommendations for purposeful weight loss in heart failure. To further explore the relationship between obesity and outcome in heart failure patients, we systematically examined the association between BMI and all- cause mortality, CV mortality and hospitalizations among patients with chronic heart failure. (more…)
Author Interviews, University Texas, Weight Research / 22.03.2015

Helen P. Hazuda, Ph.D. Professor of Medicine Division of Nephrology Department of Medicine University of Texas Health Science Center at San Antonio San Antonio, TXMedicalResearch.com Interview with: Helen P. Hazuda, Ph.D. Professor of Medicine Division of Nephrology Department of Medicine University of Texas Health Science Center at San Antonio San Antonio, TX Medical Research: What is the background for this study? What are the main findings? Dr. Hazuda: The long-term effects of diet soda consumption on health outcomes is unclear, and studies in both humans and animals have raised concerns about their potentially harmful health effects including weight gain and increased cardiometabolic risk.  Most human studies have focused on middle-aged or younger adults, rather than focusing specifically on people 65 years and older, a rapidly growing segment of the U.S. population that has a disproportionately high burden of cardiometabolic disease and associated healthcare costs.  Therefore, our study examined prospectively the association between diet soda intake and long-term change in waist circumference in a biethnic cohort of older (65+ years)  Mexican American and European American participants in the San Antonio Longitudinal Study of Aging (SALSA). SALSA included a baseline examination (1992 – 1996) and three follow-up examinations (2000-2001, 2001-2003, and 2003-2004).  The total follow-up period averaged 9.4 years.  Diet soda intake, waist circumference (WC), height and weight were measured at each examination along with sociodemographic factors, leisure physical activity, diabetes mellitus, smoking, and length of follow-up. The main finding is that over the total 9.4-year SALSA follow-up period and after adjustment for multiple potential confounders, daily diet soda users (1+ diet sodas/day) experienced an increase in  waist circumference of 3.2 inches, while occasional diet soda users (>.05 < 1 diet soda/day) experienced a  waist circumference increase of 1.8 inches, and nonusers of diet soda experienced a WC increase of 0.8 inches.  Thus, there was a striking dose-response relationship between chronic diet soda intake and long-term increases in waist circumference. (more…)
Author Interviews, Heart Disease, Weight Research / 18.03.2015

Dr Rajeev Kumar Pathak MBBS, FRACP Cardiologist and Electrophysiology Fellow Centre for Heart Rhythm Disorders | University of Adelaide Cardiovascular Investigation Unit | Royal Adelaide Hospital Adelaide AustraliaMedicalResearch.com Interview with: Dr Rajeev Kumar Pathak MBBS, FRACP Cardiologist and Electrophysiology Fellow Centre for Heart Rhythm Disorders | University of Adelaide Cardiovascular Investigation Unit | Royal Adelaide Hospital Adelaide Australia Medical Research: What is the background for this study? What are the main findings? Response: Obesity and atrial fibrillation (AF) are dual epidemics that frequently coexist. Weight-loss reduces atrial fibrillation burden; however, whether this is sustained, has a dose effect or is influenced by weight-fluctuation is not known. In this study we evaluated the  long-term impact of weight-loss and weight-fluctuation on rhythm control in obese individuals with atrial fibrillation. (more…)
Author Interviews, Weight Research / 14.03.2015

Harold P. Erickson Ph.D. James B. Duke Professor, Department of Cell Biology Duke Univ. Med. Center Durham, NC 27710MedicalResearch.com Interview with: Harold P. Erickson Ph.D. James B. Duke Professor, Department of Cell Biology Duke Univ. Med. Center Durham, NC  27710 MedicalResearch: What is the background for this study? Dr. Erickson: In Jan 2012 a paper reported the discovery of irisin, a hormone reportedly lopped off a precursor in muscle and sent through the bloodstream to fat tissue, where it turned white fat into brown fat. Brown fat burns calories, and is what hibernating animals – and even human babies -- use to keep warm. Turning on brown fat had exciting promise for obesity, diabetes, etc. Dozens of labs around the world jumped on the discovery and started trials in animals and humans of how irisin levels in blood were altered by exercise and a variety of metabolic challenges. MedicalResearch: What are the main findings? Early reports. Dr. Erickson: The follow-up studies from different labs reported a huge range of values for the level of irisin in blood, so they could not all be right. And most of them failed to find any significant effect of exercise. In 2013 two papers criticized the irisin study. A commentary article by Harold Erickson (Adipocyte 2:289-93) reported two substantial flaws in the original study. A research paper by S. Raschke, J. Eckel and colleagues (PloS one 8:e73680) concluded that humans did not make significant amount of irisin. The human gene for irisin has a deleterious mutation in the start codon, and Raschke et al showed that this reduced irisin expression to only 1% the level with the normal start. These two reports may have slowed new labs entering the field, but many groups already invested continued to publish. (more…)
Author Interviews, Endocrinology, Weight Research / 11.03.2015

Elizabeth A. Lawson, M.D., M.M.Sc. Assistant Professor of Medicine Harvard Medical School Director, Interdisciplinary Oxytocin Research Program Neuroendocrine Unit Massachusetts General Hospital Boston, MA 02114MedicalResearch.com Interview with: Elizabeth A. Lawson, M.D., M.M.Sc. Assistant Professor of Medicine Harvard Medical School Director, Interdisciplinary Oxytocin Research Program Neuroendocrine Unit Massachusetts General Hospital Boston, MA 02114 Medical Research: What is the background for this study? What are the main findings? Response: Oxytocin is a hormone produced in the brain that has been shown to reduce food intake in animal studies. The role of oxytocin on appetite and food consumption in humans is not well understood. We therefore performed a randomized, placebo controlled cross-over study of single dose administration of intranasal oxytocin (Syntocinon, Novartis) in healthy men. Subjects presented fasting in the early morning and were randomized to receive 24 IU intranasal oxytocin or placebo. They selected breakfast from a menu and were offered double portions. The caloric content of the food they ate was calculated. They returned for a second visit, which was the same except for this time, they received the other treatment (placebo or oxytocin). There was no difference in how much food the men reported eating in the three days leading up to each of the study visits. On average, the men ate 122 fewer calories and about 9 grams less fat after receiving oxytocin compared to placebo. There was also evidence that oxytocin resulted in greater use of fat as a fuel for the body, and improved insulin sensitivity. (more…)
Author Interviews, Nutrition, Weight Research / 06.03.2015

Frances M. Sladek, Ph.D. Professor of Cell Biology and Toxicologist Associate Director, UCR Stem Cell Center Department of Cell Biology and Neuroscience University of California Riverside, CA 92521-0314MedicalResearch.com Interview with: Frances M. Sladek, Ph.D. Professor of Cell Biology and Toxicologist Associate Director, UCR Stem Cell Center Department of Cell Biology and Neuroscience University of California Riverside, CA 92521-0314 Medical Research: What is the background for this study? What are the main findings? Dr. Sladek: In 2011 Blasbalg et al reported in the American Journal of Clinical Nutrition that the consumption of soybean oil was the component of the American diet that had changed the most since the early 1900s. It had in fact increased 1000-fold. Soybean oil is currently not only the main type of vegetable oil used in the U.S. but soybean meal is a major component of the diet of the animals such as cows and pigs, resulting in changes in the fatty acid composition of animal fat. Soybean oil is also increasingly being used worldwide: 40 million tons were produced in 2007 alone. In our previous study we found that a high fat diet containing comparable amounts of soybean oil to what Americans are currently consuming caused mice to become obese, diabetic and insulin resistant and to have large lipid droplets and hepatocyte ballooning in their livers. Others had found similar results and proposed that linoleic acid (an omega 6 polyunsaturated fat) that makes up >55% of the oil was responsible for the negative metabolic effects. DuPont recently generated a genetically modified  soybean oil  that had reduced levels of linoleic acid and hence less of a tendency to generate trans fats. This oil (called Plenish) came onto the market for the first time in 2014. The fatty acid composition of Plenish is similar to that of olive oil (low linoleic acid and high oleic acid), which is a major component of the healthy Mediterranean diet. The implication, therefore, is that Plenish is healthier than conventional soybean oil but that has not been formally proven. In the current study, we found that while a high fat diet containing Plenish also induced obesity, glucose intolerance and fatty liver, it did not induce insulin resistance as did the conventional soybean oil. It also induced somewhat less fat accumulation. Finally, we compared the diet enriched in soybean oil to an isocaloric diet that contained the same amount of total fat (40%kcal, Americans consume 34-37% fat) but with 90% of the fat from coconut oil. Those animals gained very little weight (13% versus 38% with the conventional soybean oil and 30% with the Plenish) and were not diabetic or insulin resistant. Their livers also had less fat than either of the two soybean oil diets and showed no signs of hepatocyte ballooning. Coconut oil has essentially no linoleic acid or other PUFAs. Our results, assuming humans respond in the same way as mice, suggest that people should avoid the consumption of too much soybean oil, either conventional or Plenish. They also show that coconut oil, which is made up of saturated fats (primarily medium chain triglycerides), is much healthier for you than soybean oil. Coconut oil has been noted previously for its beneficial health effects. (more…)
Author Interviews, Nutrition, NYU, Pediatrics, Weight Research / 26.02.2015

Brian Elbel, PhD, MPH Associate Professor, Department of Population Health; Associate Professor, Department of Medicine Population Health NYU School of MedicineMedicalResearch.com Interview with: Brian Elbel, PhD, MPH Associate Professor, Department of Population Health; Associate Professor, Department of Medicine Population Health NYU School of Medicine Medical Research: What is the background for this study? What are the main findings? Dr. Elbel: This study tried to determine whether a new supermarket that received tax and zoning credits from New York City, locating in a high need area, impacted healthy eating for children.  No previous controlled study has looked at children, and supermarkets are tool being increasingly used to improve healthy eating.  We did not find, at least one year after the store opened, any appreciable change in shopping or eating. (more…)
Author Interviews, BMJ, NIH, Pediatrics, Weight Research / 21.02.2015

MedicalResearch.com Interview with: Yeyi Zhu, PhD IRTA Postdoctoral Fellow Epidemiology Branch Division of Intramural Population Health Research Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH MedicalResearch: What is the background for this study? What are the main findings? Dr. Zhu: Currently in the US, nearly two thirds of reproductive-aged women are overweight or obese. Moreover, the amount of weight gained during pregnancy can have immediate and long-lasting impacts on health of a woman and her infant. Previous evidence implicates that excessive gestational weight gain above the Institute of Medicine guidelines is related to high birthweight (>4000 g), a marker of intrauterine over-nutrition which may impose a greater risk of offspring’s obesity and metabolic diseases in later life. Given that more than one third of children and adolescents are overweight or obese in the US, it is of great public health significance to improve our understanding of determinants and mediators of childhood obesity. The length of breast feeding and age at introduction of solid foods are infant feeding practices that are potentially modifiable in early life. We therefore examined whether birthweight and infant feeding practices, specifically length of breast feeding, mediate the relationship between maternal gestational weight gain and childhood growth in the National Children’s Study Formative Research in Anthropometry, a cross-sectional multi-ethnic study of 1387 mothers and their children aged 0-5.9 years in the US (2011-2012). We illustrated that the intergenerational relationship between maternal gestational weight gain and early childhood growth (i.e., z scores for weight-for-age, weight-for-height, and body mass index-for-age) largely acts through birthweight rather than directly on childhood growth. Further, given the negative association of breastfeeding duration with childhood anthropometrics, longer length of breastfeeding suppressed the positive associations of gestational weight gain and birthweight with childhood growth. In addition, analysis by ethnicity revealed that these associations were only significant in non-Hispanic White and non-Hispanic Black participants as opposed to Hispanics and other ethnicities. (more…)
Author Interviews, Diabetes, Exercise - Fitness, Pain Research, Weight Research / 20.02.2015

Dan White PT , ScD, Msc University of DelawareMedicalResearch.com Interview with: Dan White PT , ScD, Msc University of Delaware Medical Research: What is the background for this study? What are the main findings? Dr. White: We know that diet and exercise are beneficial to reduce knee pain, however it is not known whether diet and exercise can actually prevent the development of knee pain in people at high risk.  We found that an intensive program of diet and exercise had a small but statistically significant protective effect with preventing the development of knee pain in overweight and obese people with diabetes. (more…)
Author Interviews, Weight Research / 17.02.2015

Dr. med. Laurence Genton, FMH Médecine Interne Médecin adjointe agrégée, chargée de cours Nutrition Clinique Hôpitaux universitaires de Genève GenèveMedicalResearch.com Interview with: Dr. med. Laurence Genton, FMH Médecine Interne Médecin adjointe agrégée, chargée de cours Nutrition Clinique Hôpitaux universitaires de Genève Genève Medical Research: What is the background for this study? What are the main findings? Response: Several studies have shown that body mass index is linked to mortality through a U- or J-curve, i.e. that a low and maybe a high body mass index are related to a higher risk of mortality in elderly people. However, body mass index consists of fat mass and fat-free mass, and the former studies cannot differentiate the impact of these body compartments. However, this differentiation may be important to guide our public health care strategies. For instance, fat and fat-free mass can both be reduced by hypocaloric diet and endurance exercise, while fat-free mass can be increased with adequate calorie and protein intakes, resistance exercise and anabolic treatments. Thus, this study aimed at evaluating the impact of fat mass and fat-free mass on mortality. We found that body mass index and body composition did not predict mortality in older women. However, a high fat-free mass was associated with a lower risk of mortality in men, even when adjusting for body mass index. (more…)
Author Interviews, JAMA, Surgical Research, Weight Research / 09.02.2015

MedicalResearch.com Interview with: Torsten Olbers MD, PhD Assistant Professor of Surgery Sahlgrenska University Hospital Gothenburg, Sweden Medical Research: What is the background for this study? What are the main findings? Dr. Olbers: Until now there has been no consensus regarding preferred bariatric procedure for patients with a body mass index (BMI) above 50 kg/m2. We report on the 5-year outcomes from a randomized clinical trial of gastric bypass and duodenal switch published online by JAMA Surgery on February 4th. (more…)