Effects of diet and lifestyle changes on atherosclerotic risk factors after 24 weeks on the Indian diet heart study

Abstract

In a randomized, single-blind, controlled trial, 621 patients were assigned either intervention diet A (group A, 310 patients) or control diet B (group B, 311 patients) for a period of 24 weeks. After 24 weeks as revealed by dietary questionnaires, group A patients received (1) a diet with a higher percentage of calories from fruits and vegetables and complex carbohydrates; (2) a higher polyunsaturated/saturated fat ratio diet; and (3) a larger amount of soluble dietary fiber, antioxidant vitamins and minerals and low saturated fat and cholesterol than group B. Group A patients also did more physical and yogic exercises than group B. Adherence to diet and exercise was obtained through questionnaires and information obtained was quantified into a formula. After 24 weeks, the overall score of diet and exercises was significantly higher in group A than in group B. There was a significant decrease in serum total cholesterol (13.3%), low-density lipoprotein cholesterol (16.9%), triglycerides (19.2%), fasting blood glucose (19.5%) and blood pressures ( 11.5 6.2 mm Hg ) in the intervention group compared with initial levels and changes in group B. The effect of exercise on the decrease in risk factors was additive. Within group A, overall score for diet and exercise was greater in 1 subset of 116 patients in the intervention group which had maximal lifestyle changes. A separate analysis of data in this subgroup revealed a greater decrease in risk factors compared with risk factor changes in the remaining 194 patients with less higher overall score; this indicated that the relation of lifestyle changes with reduction in risk factors may be of causal nature. It is possible that diet and physical inactivity may be important in the development of risk factors for coronary artery disease, and lifestyle changes may reverse these risk factors within 24 weeks.