Dietary fat and the control of energy intake: evaluating the effects of fat on meal size and postmeal satiety.
Three separate experiments in lean subjects confirmed that a 1.52-MJ (362-kcal) carbohydrate supplement at breakfast suppressed appetite 90 min later but had no effect on a test meal given after 270 min. A 1.52-MJ (362-kcal) fat supplement produced no detectable action on measures of appetite at any time point. Therefore, fat and carbohydrate do not have identical effects on the appetite profile. In a further study in obese subjects, a novel experimental design was used to assess the satiating efficiency and compensatory response of fat. Eating from a range of either high-fat or high-carbohydrate foods, obese subjects voluntarily consumed twice as much energy from the fat items, thereby indicating a weak action of fat on satiation. In turn, this large intake of fat exerted a disproportionately weak effect on satiety. These studies suggest that the appetite-control system may have only weak inhibitory mechanisms to prevent the passive overconsumption of dietary fat. The results indicate how this action could induce a positive energy balance and lead to a gradual upward drift in body mass index.
Blundell
J E
JE
Psychology Department, University of Leeds, UK.
Burley
V J
VJ
Cotton
J R
JR
Lawton
C L
CL
D000704:Analysis of Variance; D001066:Appetite / Q000502:physiology*; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D004041:Dietary Fats / Q000008:administration & dosage*; D002149:Energy Intake; D005260:Female; D006801:Humans; D008297:Male; D009765:Obesity / Q000503:physiopathology*; D012528:Satiety Response / Q000502:physiology*; D013997:Time Factors
D004040:Dietary Carbohydrates; D004041:Dietary Fats