PILOT -- EFFECTS OF DIET ON CARDIOVASCULAR RISK

University Of North Carolina Chapel Hill, Chapel Hill NC

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Linked publications & trials

Abstract

African American women suffer disproportionately from diabetes and its cardiovascular complications. For African American women with diabetes (with high prevalence of overweight and CHD risk), research is needed to determine how best to improve lipid profiles (particularly, LDL- and HDL-cholesterol), through dietary patterns that are palatable and promote a higher level of compliance than the current high carbohydrate low fat (HCLF) diet prescription. While recent studies among patients with diabetes have shown positive metabolic effects of diets high in monounsaturated fatty acids (HMUFA), none have included African Americans. The overall aim of this pilot study is to assess the acceptability and monitor the metabolic effects of a HMUFA vs. HCLF diet in a sample of free-living African American women with type 2 diabetes. A randomized crossover design is proposed for evaluating the acceptability and metabolic effects of the study diets. Twenty African American women with type 2 diabetes will be recruited from 1 primary health care facility. At baseline, measures of diet, weight, height, blood pressure, blood lipids, red blood cell (RBC) membrane fatty acids, and hemoglobin A1c (HbA1c) will be collected. Randomization to 1 of the 2 study diets will follow a 1-week run-in period, where participants will be evaluated for compliance with the diet protocols. Study diets will be isocaloric to the diet consumed during the run-in period. The study diets will have the following composition (as a percentage of total calories): HMUFA - 40% carbohydrates, 20% protein, 40% fat, 9% saturated, 21% monounsaturated, and 10% polyunsaturated; HCLF - 55% carbqhydrates, 20% protein, 25% fat, 9% saturated, 10% monounsaturated, and 6% polyunsaturated. Both diets will have < 300 mg/d cholesterol and similar levels of dietary fiber. Daily menus specifying foods and portions to be consumed for 3 meals + 1-2 snacks will be provided to each participant. Foods in both diets will be the same except for key foods high in monounsaturated fats added to the menus for the HMUFA study diet; all key foods will be supplied to study participants. After 6 weeks on the 1st study diet, participants will return to an isocaloric usual diet for 2 weeks, then crossover to the 2nd study diet. Following each 6-week diet period, measures taken at baseline will be repeated. A questionnaire will be used to evaluate the acceptability of the HMUFA diet relative to the HCLF diet in terms of palatability, preference, ease of preparation, satiety, etc.