SATIETY POWER OF DIETARY-FAT - A NEW APPRAISAL

Accumulating evidence suggests that a good way to compare the satiety power of meals with different compositions or energy contents is to me asure the onset latency of the next meal when freely requested by subj ects deprived of any time cues. This study was performed in normal-wei ght young men (aged 19-24 y) isolated from time cues. At sessions 1 an d 2, we studied the effects of two high-carbohydrate pasta lunches wit h either 50 g low-energy butter substitute (lunch A) or 50 g butter (l unch B) on hunger ratings, on the latency of the dinner request, and o n energy and nutrient intakes at the offered ad libitum dinner. Sessio ns 3 and 4 were designed to examine the effects of the two lunches on the postlunch and predinner profiles of plasma glucose, insulin, gluca gon, and lipids; consequences on the metabolic and hormonal responses to the fixed dinner offered on request also were tested. The addition of 1588 kJ butter to the pasta lunch compared with the addition of 67 kJ butter substitute had no effect on hunger ratings but significantly delayed the onset of dinner by approximate to 38 min; however, neithe r energy intake nor nutrient intakes were different. The high-fat lunc h led to a slightly different postlunch plasma glucose concentration p rofile but, as expected, to higher plasma triacylglycerol and fatty ac id concentrations. The high-fat lunch also led to postdinner glucose i ntolerance with normal insulin and high fatty acid concentrations that may help explain the partial and delayed adjustment in energy intake after a high-fat meal as reported by some studies.