Beneficial metabolic effects of regular meal frequency on dietary thermogenesis, insulin sensitivity, and fasting lipid profiles in healthy obese women.

BACKGROUND Although a regular meal pattern is recommended for obese people, its effects on energy metabolism have not been examined. OBJECTIVE We investigated whether a regular meal frequency affects energy intake (EI), energy expenditure, or circulating insulin, glucose, and lipid concentrations in healthy obese women. DESIGN Ten women [x +/- SD body mass index (in kg/m(2)): 37.1 +/- 4.8] participated in a randomized crossover trial. In phase 1 (14 d), the subjects consumed their normal diet on 6 occasions/d (regular meal pattern) or followed a variable meal frequency (3-9 meals/d, irregular meal pattern). In phase 2 (14 d), the subjects followed the alternative pattern. At the start and end of each phase, a test meal was fed, and blood glucose, lipid, and insulin concentrations were determined before and for 3 h after (glucose and insulin only) the test meal. Subjects recorded their food intake on 3 d during each phase. The thermogenic response to the test meal was ascertained by indirect calorimetry. RESULTS Regular eating was associated with lower EI (P < 0.01), greater postprandial thermogenesis (P < 0.01), and lower fasting total (4.16 compared with 4.30 mmol/L; P < 0.01) and LDL (2.46 compared with 2.60 mmol/L; P < 0.02) cholesterol. Fasting glucose and insulin values were not affected by meal pattern, but peak insulin concentrations and area under the curve of insulin responses to the test meal were lower after the regular than after the irregular meal pattern (P < 0.01 and 0.02, respectively). CONCLUSION Regular eating has beneficial effects on fasting lipid and postprandial insulin profiles and thermogenesis.