The edition also reviews the link between Vitamin D deficiency and obesity, particularly in pregnancy, and presents evidence that low-calorie sweeteners used in T2D prevention and management may have advantages for glycemic control, especially in small doses.
Matthew Goodwin, Journal Director for Touch Medical Media's Endocrinology Division, said "In recent decades, the incidence of obesity and Type 2 diabetes has risen to epidemic levels with significant implications for healthcare systems around the world. This issue of US Endocrinology in part addresses these inter-related health concerns through the lens of non-medical interventions, demonstrating the range of low-cost options that can be readily adopted to augment current therapeutic approaches in managing diabetes."
Applying the Principle of Energy Balance to Combat Obesity, Prevent Type 2 Diabetes Using the lens of energy balance - which combines food intake, energy expended through physical activity and energy (fat) storage - to answer the question of why so many weight loss regimens are unsuccessful, a featured paper by James O. Hill, PhD, and colleagues at the Anschutz Health and Wellness Center find the majority of diets emphasizing food restriction produce an "unregulated zone" of energy balance, triggering the body's natural defenses towards preserving existing body weight, such as increased hunger and a drop in the resting metabolic rate (RMR). For dieters achieving a 10% weight loss, the decline in RMR translates into a reduced calorie requirement of 170-250 kcal per day whereas a 20% weight loss requires a drop of 325-480 kcal a day just to maintain the new body weight. Accordingly, the researchers estimate that one-third to two-thirds of dieters who only restrict food intake to lose weight will ultimately regain more pounds than they lose through these regimens.
The researchers also used the principle of energy balance to explain what they call "the ratchet effect" where small, consistent increases in calorie intake in adults lead to gradual weight gain over time. Employing a modeling approach to apply these small effects to the U.S. population, the researchers conclude that an average daily imbalance between energy intake and expenditure of about 10 kcal is responsible for the nation's obesity epidemic. Therefore, the researchers advance the concept of a "regulated zone" of energy balance accomplished by combining small deficits in food intake with an increase in physical activity levels to reduce positive energy balance by 100 kcal a day. This amount is equivalent to the decrease in the U.S. daily occupation-related energy expenditure over the last 50 years resulting from increased urbanization, industrialization and use of mechanized transportation.
Implementing a New Model to Prevent Childhood Obesity
While the Anschutz Health and Wellness Center researchers focused on reducing the burden of adult obesity, a paper by the EPODE (Ensemble Prevenons l'Obesite Des Enfants) European Network Coordinating Team quantifies the impact of the EPODE methodology, which utilizes a multi-stakeholder approach at the community level, in reducing obesity among children ages 0 to 12 years in France and Belgium and reducing the socioeconomic gap in obesity prevalence in France. Results from eight French EPODE pilot towns showed a 9.12% decrease in overweight and obesity in children ages 4 and 5 years and 11 and 12 years between 2005 and 2009 whereas pilots in two Belgium towns in 2007 and 2008 reported a 22% decrease in the prevalence of obesity among nursery school children. The EPODE methodology is also credited with a downward trend of 2% in the prevalence of childhood obesity among French children attending schools in deprived areas compared with an increase in obesity prevalence among French children from disadvantaged households at the national level. Based on these findings, the EPODE methodology has now been implemented in a number of countries worldwide.
Assessing the Role of Low-Calorie Sweeteners in Diabetes Management
Addressing the concern that consumption of fructose is fueling the diabetes epidemic, new research by Craig A. Johnson, PhD, Brian Stevens, BSc, and John Foreyt, PhD finds no conclusive evidence that fructose is harmful and may even have advantages for glycemic control, especially at small doses. However, because added sugars are a source of increased carbohydrate intake, the researchers examined the benefits of replacing added sugars with low-calorie sweeteners (LCS), which contain fewer calories and do not raise blood glucose levels, improving the ability for individuals to prevent and control their weight. Based on a review of multiple studies, the reviewers conclude that LCS can help improve oral hygiene and dental care and is a viable way for individuals who do not have T2D to manage reactive hyperglycemia by preventing the excessive sugar intake that can lead to increased sugar secretion. The reviewers also document the safety of LCS for the prevention and treatment of diabetes and weight loss, reporting that low-calorie sweeteners have no effect on insulin and hormone secretion and have not been shown to increase appetite. Moreover, the researchers document the findings from randomly controlled trials in humans that suggest the use of LCS may increase adherence to weight loss regimens and improve bodyweight and weight loss maintenance over time. Based on these findings, the researchers conclude that LCS can serve an important role in diabetes prevention and management and offer a practical method for promoting a reduction in caloric intake.
New Findings on Vitamin D Deficiency and Its Implications for Obesity and Type 2 Diabetes
Because Vitamin D is an important metabolic regulator and is thought to play an important role in insulin resistance and the regulation of blood glucose levels, two papers explore the impact of Vitamin D deficiency on insulin resistance, metabolic syndrome and obesity, especially during pregnancy. Examining the state of the science on Vitamin D deficiency (hypovitaminosis D), researchers at the Sao Paolo Medical School confirm an inverse association between body fat content and Vitamin D levels, although insufficient evidence exists to determine if supplementation is required in the obese population. In the interim, the researchers present the findings from recent studies, suggesting that obese individuals require higher doses of Vitamin D than the general population for optimal health. One study recommends that obese individuals take two to three times more Vitamin D than individuals of the same age who are at a normal weight.
Complementing these findings, a paper by Trixie McAree, MSc, RN, a midwife with the North West London Hospital Trust, reports that Vitamin D deficiency and obesity have shared risks for morbidity and mortality, including cardiovascular disease, diabetes, respiratory conditions, cancer and musculoskeletal disease and this relationship likely applies to pregnancy, where small studies have found that women carrying extra weight may not be passing along enough Vitamin D to the their offspring. Accordingly, the paper calls for large-scale clinical studies to determine the timing and optimal dosing for supplementation during pregnancy but notes that in the interim, the UK National Institute for Health and Care Excellence (NICE) and many professional societies advise obese pregnant women to increase their Vitamin D levels by taking 10 micrograms per day in the form of a multivitamin supplement.