Research Focus: Nutritional analysis, menu planning, and meal preparation for feeding studies requiring nutrient analysis and meals/food for participants.
Current Research Project
2008 - 2011 NIH /NIDDK grant
April 2009 - March 2013, $500,000 awarded over 4 years
Primary investigator: Ted Weiss, Saint Louis University,
Research Title: Caloric Restriction, Exercise, and Glucoregulation in Humans
Feeding coordinator: Kathy Kress
Developed menu and menu analysis, and coordinate all aspects of food procurement and preparation for feeding component of study.
Study Design: randomized trial that compares the effects of weight loss induced by calorie restriction (CR), exercise (EX), and CR+EX on glucoregulatory function and related mechanisms. Twenty subjects were randomized to each of the study groups with stratification for sex. Outcomes will be assessed at the beginning and end of the intervention. Participants whose weight did not meet desired weight loss for 2 consecutive weeks were given 5-7 days of outpatient feeding on an energy restricted diet. The meals were prepared in the Nutrition and Dietetics Department kitchens at Saint Louis University. The composition of the diet was 55% of energy as carbohydrate, 20% protein, and 25% fat. The energy level of the diet was individualized to contain 20% less energy than the baseline. The meals consisted of common foods that were selected based on each participant's preferences. Meals were carried out in coolers that participants exchanged every 1 or 2 days during the feeding period.
Objective: The proposed study will provide valuable information about how weight loss through a combination of caloric restriction and exercise might provide greater health benefits than similar weight losses through caloric restriction alone or exercise alone. This information is especially important in light of the current epidemics of overweight, obesity, and diabetes. The study will test the hypothesis that caloric restriction improves insulin sensitivity through a mechanism that is independent of weight loss.
Background: Glucose intolerance, insulin resistance, and type 2 diabetes are becoming increasingly prevalent in the United States and worldwide. Consequently, there is a need to understand the etiology of these conditions and to identify effective treatments to improve insulin action and reduce type 2 diabetes risk. CR and EX both improve glucose tolerance and insulin action and reduce the risk of type 2 diabetes and as a result, are commonly recommended for preventing and treating hyperglycemia and insulin resistance. However, despite these clinical recommendations, it is not known if some of the benefits from CR and EX are mechanistically independent and therefore additive.
Outcomes: This is a pilot study whose primary goal of all study interventions is to induce a 6% weight loss. Before and after the intervention, glucose tolerance and insulin action will be assessed by using a 2-hr oral FSOGTT to determine if greater health benefits occur when CR and EX are combined.
Grant/Sponsor: National Institute of Health / NIDDK