MedicalResearch.com Interview with:
Margaret C. Campbell, Phd | Professor | Marketing
Chair, Doctoral Curriculum Program Committee
437 Leeds School of Business
University of Colorado at Boulder
Boulder, CO 80309-0419
Medical Research: What is the background for this study? What are the main findings?
Dr. Campbell: People try to maintain healthy body weights, attain academic and career success, save money for a car, a house, or retirement, and achieve a host of other goals that require repeated, goal-consistent behaviors. Unfortunately, consumers’ efforts often fall short. For example, 68% of Americans are overweight (Weight Control Information Network 2010), 46% who begin college do not graduate within six years (Associated Press 2006), and although 93% say that saving for retirement is important, only about 60% are actually saving (TIAA-CREF 2010) and approximately 50% have accumulated less than $25,000 (Helman, VanDehrei and Copeland 2007). Understanding goal pursuit and consumers’ choices to continue effort toward a goal that requires repeated goal-consistent behaviors is thus important. People need to be able to make progress on important goals that substantially impact their quality of life.
Monitoring the influence of behavior on distance from a focal goal has been identified as important for successful goal pursuit - such as weight loss. In seven experiments, we find that people tend to have a “progress bias” such that they perceive that goal-consistent behaviors (such as avoiding eating a piece of cake) help progress more than equivalent-sized goal-inconsistent behaviors (such as eating a piece of cake) hurt progress. An experiment on exercise and eating shows that the progress bias can lead to poor understanding of progress and thus, premature release of the goal. In this study, the progress bias resulted in people with a goal of expending more calories than they consumed ended up consuming more than they expended.
MedicalResearch.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. MedicalResearch.com Interview with: Dr. Alex Johnstone PhD Rowett Institute of Nutrition and Health Aberdeen Medical Research: What is the background for this study? Response: Previous...
MedicalResearch.com Interview with:
Colette Nicole Miller FDN
Department of Foods and Nutrition
Edgar L. Rhodes Center for Animal and Dairy Science
University of Georgia, Athens, Georgia
Medical Research: What is the background for this study?
Response: Our laboratory has been interested for quite some time in the relationship that natural, plant-derived compounds have on various tissues in the body. Both bone and adipocytes are derived from the same progenitor cell, mesenchymal stem cells. Thus, if a drug or compound affects one type of cell, it may affect both. When women transition through menopause, and see a reduction in their female sex hormones like estrogen, they can see adverse changes in both how much fat they store and their bone density. Thus our lab is interested in compounds that can be used to prevent the bone loss and visceral adipogenesis that menopausal women often experience. Previous work both in vivo and in vitro has shown that phytochemicals have synergistic effects and thus can ultimately work together to reduce the dosages needed to promote overall health. Through this work we have identified a combination of genistein, resveratrol, quercetin and Vitamin D that improve bone density in addition to promoting apoptosis of adipocytes. However, the health of the liver had never been addressed with our phytochemical blend. We know that supplements are sometimes toxic to the liver for many different reasons. Thus, it was very important for us to address the toxicity and potential risk of non-alcoholic fatty liver disease with our phytochemical blend in a menopausal rat model.
MedicalResearch.com Interview with:
William Mair, Ph.D Assistant Professor
Department of Genetics and Complex Diseases
Harvard T. H Chan School of Public Health
Boston, MA 02115
MedicalResearch: What is the background for this study? What are the main findings?
Dr. Mair: Dietary restriction, the reduction of food intake without malnutrition has been known for 80 years to prolong lifespan in organisms ranging from single celled yeast to non human primates, and early signs suggest improvement of metabolic parameters in patients undergoing clinical trials. However, negative side effects associated with low calorie intake remain, and compliance and lifestyle factors make it an unappealing therapeutic. Since calorie restriction (CR) can have remarkable protective effects against multiple age onset diseases in mouse models - ranging from cancer to neurodegeneration to metabolic disease - finding molecular mechanisms though which calorie restriction functions might provide novel therapeutic targets that promote healthy aging. Using a model system, the nematode worm C. elegans, we show that perception of energy intake in the nervous system may be as critical for the effects of low energy on aging as actual calorie intake itself. Animals expressing an active form of a protein called AMPK, which is a cellular energy sensor, were long lived despite eating normally but this longevity could be turned off or on by changes to a neurotransmitter in just a few neurons. This suggests that therapeutic targets that modulate the perception of energy status in the nervous system might provide novel ways to gain the benefit of calorie restriction and promote healthy aging.
MedicalResearch.com Interview with:
Kari Johansson, PhD
Department of Medicine Solna, Karolinska Institutet
Clinical Epidemiology
Karolinska University Hospital
Stockholm, Sweden
MedicalResearch: What is the background for this study? What are the main findings?
Dr. Johannson: The number of women who are obese in early pregnancy has increased dramatically over the last decades. Consequently, there has been a dramatic rise in the number of women becoming pregnant after bariatric surgery. In Sweden the number of births of women with a history of bariatric surgery has increased from 150 (≈0.15%) to more than 500 (0.5%) per year between 2006 and 2011. The positive effects of bariatric surgery on health outcomes, such as diabetes and cardiovascular disease, are reasonably well-studied, but less is known about the effects on pregnancy and perinatal outcomes. We therefore conducted a population-based study, using data from nationwide Swedish registers.
The main findings are that women who had a history of bariatric surgery were much less likely to develop gestational diabetes (2% compared to 7%; P<0.001) and give birth to large-for-gestational age babies (9% vs 22%; P<0.001). On the other hand, the operated women were twice as likely to give birth to babies who were small for gestational age (16% vs 8%), and have pregnancies of shorter duration (273 vs 277.5; P<0.001).
MedicalResearch.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.
MedicalResearch.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.
MedicalResearch.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.
MedicalResearch.com Interview with:
Jonetta L. Johnson, PhD, MPH
Epidemiologist
Division of Reproductive Health, CDC.
Medical Research: What is the background for this study?
Dr. Johnson: Achieving adequate gestational weight gain (GWG) is important for optimal health of the infant and mother. Women who gain below or above Institute of Medicine (IOM) recommendations are more likely to experience maternal complications and negative infant birth outcomes. Realizing the importance of gestational weight gain to maternal and infant health, the IOM established recommendations for gestational weight gain based on a woman’s prepregnancy body mass index (BMI) in 1990 and updated them in 2009. Trends in GWG are particularly of interest since prepregnancy BMI has increased over time in the U.S and little data was available on how gestational weight gain has changed over time.
Medical Research: What are the main findings?
Dr. Johnson: Our findings show that from 2000-2009, the majority of women did not gain weight within IOM GWG recommendations and that women were more likely to gain outside recommendations in more recent years. In fact, from 2000–2009, there was a gradual decrease (1.0 percentage point every 2 years) in women gaining within IOM gestational weight gain recommendations and a gradual increase (0.8 percentage points every 2 years) in women gaining above IOM recommendations while the percentage of women gaining weight below IOM recommendations remained relatively constant. Although there were slight differences in mean gestational weight gain by BMI group, gestational weight gain was about 31 pounds on average. The decreasing percentage of women gaining within IOM recommendations during our study period may be influenced by increases in prepregnancy BMI during the same time period because women in higher BMI groups are recommended to gain less weight during pregnancy compared to women in lower BMI groups. Thus, even with no change in gestational weight gain over time, an increase in the proportion of women who are obese could result in a decrease in the proportion of women gaining within gestational weight gain recommendations.
MedicalResearch.com Interview with:
Joanna Holbrook PhD
Senior Principal Investigator - Systems Biology
Singapore Institute for Clinical Sciences
Brenner Centre for Molecular Medicine
Singapore
Medical Research: What is the background for this study?
Dr. Holbrook: Bacteria in the human gut may influence many aspects of our health; however, it is not fully known what determines the composition of the gut microbiota. Rapid bacterial colonisation of the infant gut could be influenced by the environment of the baby before birth, and microbiota content has been associated with the development of obesity and insulin resistance.
Medical Research: What are the main findings?
Dr. Holbrook: The rate of bacterial colonisation of the gut is influenced by external factors such as the method of delivery and duration of gestation. Also, infants with a mature gut bacteria profile at an early age gained normal levels of body fat, while infants with less mature gut bacteria profiles displayed a tendency to gain lower levels of body fat at the age of 18 months, indicating that gut bacteria could be related to normal development and healthy weight gain.
MedicalResearch.com Interview with:
Xuemei Sui, MD, MPH, PhD
Assistant Professor Department of Exercise Science
Graduate Director Division of Health Aspects of Physical Activity
Arnold School of Public Health University of South Carolina
Columbia, SC 29208
Medical Research: What is the background for this study?
Dr. Sui: Previous studies have established that low levels of cardiorespiratory fitness (CRF), an indicator of regular physical activity, and body compositions with higher fat mass serve as risk factors for cardiovascular disease and predictors of deaths related to cardiovascular disease. These studies have examined long-term trends of fatness (i.e., body fat) and cardiorespiratory fitness in children, adolescents and men, but few have looked at these factors in female populations. Therefore, the aim of this study was to investigate secular change of cardiorespiratory fitness and body composition during 35 years in a large sample of women enrolled in the Aerobics Center Longitudinal Study.
13 037 women aged 20 to 64 were enrolled in our study from January first, 1970, through December 31st, 2004. We divided our participants into 2 age groups, and divided 35 years into 7 time groups. Cardiorespiratory fitness was assessed by maximal treadmill testing using a modified Balke protocol, and the percentage of body fat was assessed by hydrostatic weighing or the sum of 7 skinfold measures, following standardized protocols. According to percent body fat, we divided body composition into fat mass and fat free mass.
Medical Research: What are the main findings?
Dr. Sui: The data showed that body mass index (BMI) increased over the 35-year period even though cardiorespiratory fitness levels rose as well. By looking at the body composition of the participants along with their BMIs, the researchers were able to observe that their body fat did not increase. This finding suggests that the weight gains that led to higher BMIs over time were not necessarily comprised of body fat. Participants may have been putting on muscle mass due to their increased physical activity, as indicated by their higher cardiorespiratory fitness.
Another interesting finding was that when leisure-time physical activity (LTPA) reaches 668.5 MET min/wk, cardiorespiratory fitness stays at a higher level. So in order to improve cardiorespiratory fitness for physically inactive women, we should encourage them to meet this level. The drift downward in cardiorespiratory fitness among women indicates the need for continuing efforts to promote their physical activity and fitness.
MedicalResearch.com Interview with:
Dr Cornelia HM van Jaarsveld and Prof Martin C Gulliford
Department of Primary Care and Public Health Sciences
King’s College London, London, UK
Medical Research: What is the background for this study? What are the main findings?
Response: Overweight and obesity in children have increased dramatically since the 1960s with important clinical and economic impacts, especially among those who become obese adults. Consequently, understanding trends in obesity is of increasing importance for monitoring population health and informing policy initiatives. Current trends suggest that a majority of the world’s population will be either overweight or obese by 2030. However, recent reports suggest that the increasing trend in overweight and obesity in children may have leveled off since 2000. But, in many countries data are based on a limited number of time points and relatively small surveys, limiting definitive conclusions and not allowing examining trends in subgroups by sex and age. Moreover, only a few countries have data on younger children (aged under 6 years).
Our study aimed to use primary care electronic health records to examine prevalence of overweight and obesity in 2 to 15 year old children in England and to compare trends over two decades, from 1994 to 2003 and from 2004 to 2013.
Medical Research: What are the main findings?
Response: We found that currently about a third of children in the UK are overweight or obese. We also found that overweight and obesity prevalence increased during decade 1 (1994-2003) but stabilized in decade 2 (2004-2013). This was observed in both sexes and the in younger age groups (2-5 year and 6-10 year). However, rates continued to increase in older children (11-15 year), albeit at a slower speed than in decade 1 (1994-2003).
MedicalResearch.com Interview with:
Sue Shapses, PhD
Professor, Department of Nutritional Sciences
Acting Chair, Department of Exercise Sciences and Sports Studies Rutgers, The State University
New Brunswick, NJ 08901-8525
MedicalResearch: What is the background for this study?
Dr. Shapses: Improving health outcomes through dieting and weight loss is encouraged for the majority of Americans who are either overweight or obese. However, while most studies show that a moderate reduction in body weight decreases obesity related comorbidities, there may also be loss of bone and muscle in older individuals. Specifically in postmenopausal women, intentional moderate weight loss results in a 1-2.5% bone loss when compared to a weight stable group. Studies in men, designed to address the effect of weight reduction at multiple bone sites, compartments and geometry, are currently lacking. In addition, while a higher body weight is associated with higher bone mass, evidence indicates that bone quality, a predictor of fracture risk, is compromised in the obese. It is possible that frequent dieting or weight cycling in these obese individuals may have deleterious effects on bone. Therefore, understanding whether bone quality changes with weight loss, is important to better predict osteoporosis risk in this population. In this controlled trial, the effect of dietary restriction on bone mineral density (BMD), geometry and strength were examined in middle aged and older obese/overweight men. In addition, we addressed whether endocrine changes associated with weight loss explain bone changes.
MedicalResearch.com interview with:
Caroline M. Apovian, MD
Chair of the Endocrine Society task force that developed “Pharmacological Management of Obesity: An Endocrine Society Clinical Practice Guideline” Boston University School of Medicine
Boston Medical Center
MedicalResearch: What is the background for this report?
Dr. Apovian: The Food and Drug Administration has approved four new anti-obesity drugs – lorcaserin, phentermine/topiramate, naltrexone/bupropion and liraglutide – in the past two years. To help clinicians navigate this changing landscape, the Endocrine Society developed its Clinical Practice Guideline to provide strategies for prescribing drugs to manage obesity and promote weight loss.
MedicalResearch: What are the main findings?
Dr. Apovian: In the Clinical Practice Guideline, the Endocrine Society recommends that diet, exercise and behavioral modifications be part of all obesity management approaches. Other tools such as weight loss medications and bariatric surgery can be combined with behavioral changes to reduce food intake and increase physical activity, in appropriate patients. Patients who have been unable to successfully lose weight and maintain a goal weight may be candidates for prescription medication if they meet the criteria on the drug’s label as well as BMI criteria (BMI greater than or equal to 30 or greater than or equal to 27 with at least one comorbidity).
Other recommendations from the CPG include:
natural course of healthy obesity over two decades we found that about half of healthy obese adults become unhealthy obese after 20 years, with a clear trend for increasing progression to ill-health over time. Healthy obese adults are also much more likely to become unhealthy obese than healthy or unhealthy non-obese adults, indicating that healthy obesity is often just a phase.
MedicalResearch.com Interview with:
David Arterburn, MD, MPH, FACP
Associate Investigator
Group Health Research Institute
Seattle, WA 98101 and
David L. Maciejewski PhD
Center for Health Services Research in Primary Care
Durham VA Medical Center, Durham, North Carolina
MedicalResearch.com: Why was this study needed?
Response: There were several reasons to conduct this study. First, although complications and death during and soon after bariatric surgery have progressively declined over the past several decades, there is simply very little long-term evidence on the survival benefits of bariatric surgery in Americans having surgical procedures that are being used today in routine practice.
Second, we felt that it was important to look at the impact of bariatric surgery among veterans because they represent an older male cohort often with multiple medical comorbidities, which is different from the typical bariatric patient in the United States, who is often younger and female.
MedicalResearch.com: How was your study conducted?
Response: We conducted a retrospective observational study using high-quality data from national Department of Veterans Affairs electronic databases and the VA Surgical Quality Improvement Program. We identified veterans who underwent bariatric surgery in VA medical centers from 2000 to 2011. Three quarters of them were men. We matched them to control patients using an algorithm that included age, sex, VA geographic region, body mass index (BMI), diabetes, and Diagnostic Cost Group. We then compared survival across bariatric patients and matched controls using Kaplan-Meier estimators and stratified, adjusted Cox proportional hazards analyses.
MedicalResearch.com: What were the main findings of your study?
Response: This study had three important results:
1) Our analysis showed no significant association between bariatric surgery and death from all causes in the first year of follow-up. In other words, having bariatric surgery was not significantly related to a veteran’s chance of dying in the first year compared to not having surgery.
2) We had an average follow-up of 6.9 years in the surgical group and 6.6 years in the matched control group. After one to five years, adjusted analyses showed significantly lower mortality in the patients who had surgery: 55% lower, with a hazard ratio of 0.45. The finding was similar at 5 or more years, with a hazard ratio of 0.47. This means that bariatric surgery was associated with lower long-term mortality – that is, better long-term survival among veterans, which is consistent with limited non-VA research that has addressed this same question.
3) Finally, we also found that the relationship between surgery and survival were similar comparing men and women, patients with and without diagnosed diabetes, and patients who had bariatric surgery before versus after year 2006.
MedicalResearch.com Interview with:
Jeffrey A. Gusenoff, MD
Associate Professor of Plastic Surgery
Co-Director, Life After Weight Loss Program
Co-Director, BodyChangers
Director, Post-Bariatric Body Contouring Fellowship
UPMC Department of Plastic Surgery
Medical Research: What is the background for this study? What are the main findings?
Dr. Gusenoff: With the rise in massive weight loss patients from bariatric surgery or diet and exercise, more patients are choosing to have a thighplasty to remove excess skin of the inner thigh. Many techniques exist for treating this, but there aren't many studies that look into the safety of these procedures in massive weight loss patients. What we found is that many patients have scars that go all the way down the thigh with a fairly high complication rate of almost 70%.
MedicalResearch.com Interview with:
Taylor S. Riall, MD, PhD
Professor, John Sealy Distinguished Chair in Clinical Research
Department of Surgery, University of Texas Medical Branch,
Galveston, TX
Medical Research: What is the background for this study? What are the main findings?
Dr. Riall: In patients who have symptoms related their gallstones – most commonly sharp right upper quadrant abdominal pain (often associated with fatty meals), nausea, and vomiting - the current recommendation is to remove the gallbladder (perform cholecystectomy). However, in older patients there are multiple factors that make this decision difficult. Older patients have more associated medical problems (like diabetes, heart disease, etc.) making elective surgery higher risk. On the flip side, older patients are at higher risk of developing complications from their gallstones, and once they do, their mortality (death from gallbladder disease) and complications increase substantially.
In recent study of Medicare beneficiaries with symptomatic gallstones, we found that fewer than 25% underwent elective removal of the gallbladder after an initial episode of pain or symptoms related to their gallbladder. We then developed a model that predicted the likelihood of these same patients requiring emergent gallstone-related complications if they did not have their gallbladder removed electively.
This information prompted the current study. We sought to determine if the patients getting their gallbladders removed were the ones at highest risk for complications. Similar to the previous study, we found that only 22% of Medicare beneficiaries in this study (a different population) underwent elective gallbladder removal. We divided patients into three groups based on our risk prediction model – those with <30% risk, 30-60% risk, and >60% risk of requiring acute gallstone-related hospitalization. Please note that while we call the <30% risk group “low” risk, a 17% chance of hospitalization is actually a significant risk – much higher than seen in other medical conditions for which surgery or other interventions may be considered.
MedicalResearch.com Interview with:
Dr. Jonathan L. Silverberg MD PhD MPH
Assistant Professor in Dermatology, Medical Social Sciences and Preventive Medicine
Northwestern University, Chicago, Illinois
Medical Research: What is the background for this study?
Dr. Silverberg: Previous studies found associations between obesity and atopic dermatitis (AD). However, little was known about the association between AD and metabolic risk factors, such as central obesity and high blood pressure.
MedicalResearch.com Interview with:
Rania Mekary, MS, Ph.D.
Harvard School of Public Health
Nutrition Department
Boston, Ma 02115
Medical Research: What is the background for this study? What are the main findings?
Dr. Mekar: Findings on weight training and waist circumference (WC) change have been controversial. Moreover, a lot of people focus on aerobic and only aerobic workout... They are not to be blamed because aerobic workout (e.g. jogging) relies mostly on fat as a source of energy while anaerobic workout (e.g. resistance) relies mostly on carbohydrates. Our study, however, showed that resistance training over the long-term was the most inversely associated with waistline change (aka abdominal fat), even more than aerobic exercise. We also justified physiologically why it is the case... It has to do with the greater Excess Post-exercise Oxygen Consumption (EPOC) as compared with aerobic training and also to the muscle adaptation and its increase in mitochondria which leads to more lipid oxidation upon engaging in anaerobic workout over the long-term.
MedicalResearch.com Interview with:
Elina Helander, PhD
Personal Health Informatics
Department of Signal Processing
Tampere University of Technology, Tampere, Finland
Medical Research: What is the background for this study? What are the main findings?
Dr. Helander: Frequent or at least regular self-weighing is a part of behavioral therapy in many weight programs. However, self-weighing frequency typically varies over time. We analyzed almost 3,000 weight observations from 40 overweight individuals that participated in a 1-year health promotion program. These individuals were instructed to weigh themselves daily but eventually had varying self-weighing frequencies. We examined how different self-weighing frequencies of the same individual were linked with weight changes.
We found that weight loss generally occurred during daily weighing. When there were longer breaks in self-weighing such as one month or more, there was a risk of weight gain. We also computed a theoretical minimum self-weighing frequency for having no weight gain that was 5.8 days in our study. That corresponds approximately weekly weighing.
MedicalResearch.com Interview with:
Mohammed Elfaramawi , MD PhD MPH MSc
Assistant Professor
Epidemiology Department
College of Public Health
University of Arkansas for Medical Sciences
Little rock, AR 72205
Medical Research: What is the background for this study? What are the main findings?
Dr. Elfaramawi: A substantial increase in prevalence of obesity has been documented globally. In the USA, overweight and obesity are the second leading cause of preventable death in the USA, affecting ∼97 million adults. Evidence has accumulated showing that visit-to-visit blood pressure variability is associated with adverse cardiovascular outcomes. This study is one of few studies which explored the relationship between obesity and visit-to-visit blood pressure variability.
MedicalResearch.com Interview with:
Dr. Richard Phipps PhD
Department of Environmental Medicine and Flaum Eye Institute,
School of Medicine and Dentistry, University of Rochester, Rochester, New York
Medical Research: What is the background for this study? What are the main findings?
Response: Obesity has risen dramatically over the past 30 years in the United States and throughout the world. Obesity increases morbidity and mortality by increasing health problems such as Type 2 diabetes, cardiovascular disease and cancer. Thus, obesity is one of our greatest challenges worldwide. Our laboratory has been studying a protein called Thy-1 for several decades. Until now its’ true function was unknown. The main finding from our research is that when cells express this protein on their surface, they are inhibited from becoming fat cells. We show in a mouse model system that mice, which lack Thy-1, and given a high fat diet, increase weight much faster than mice that express Thy-1. These mice that lack Thy-1, also have increased levels of many proinflammatory mediators in their blood. In human cells, those that express high levels of Thy-1 are blocked in their ability to become fat cells, unlike the human cells from different tissues that do not express Thy-1. Thus, the main finding is that learning how to manipulate Thy-1 expression could lead to reduced fat cells and reduced fat production. Not only is this an important finding for obesity, but there are many human diseases that are caused by excess fat production in organs, such as, the orbit of the eye, the liver, and the bone marrow.