Dietary Epigenetic Factors Influencing Central Obesity

Background: Central obesity, a major public health concern in the Asia-Pacific region, is a result of genetic predisposition as well as epigenetic influences. Nutritional factors influence obesity, through the calorie intake and modulating gene expression. Objectives: To conduct a systematic review of the efficacy of dietary interventions through clinical trials, in the management of obesity. Methods: PubMed and Google Scholar databases were searched for 20 years ending December 30, 2014, to find metaanalyses, systematic reviews, and randomized, placebo-controlled studies for central obesity-related clinical trials. The search terms were “central obesity” and “dietary interventions” or “calorie recommendation”. All clinical trials on the effects of dietary interventions with the key outcome measures as change in BMI, waist-hip circumference and body fat were included. Results: Several dietary regimens with varying macronutrients composition are used to combat obesity, such as low-calorie diets, very low-calorie diets (VLCD), low-fat diets, high-fiber diets, low-carbohydrate diets, low glycemic index (GI) diets and plant-based diets. However, very low-calorie-ketogenic and high protein diets have demonstrable significant adverse health effects. Conclusion: The studies reviewed show promise of benefits with changes in epigenetic dietary factors. To draw definite conclusions, there is a need for more long-term studies, with larger sample sizes; and clinical interventions trials, to minimize the risk of false positives and confounding factors influencing the results.