Energy and macronutrient composition of breakfast affect gastric emptying of lunch and subsequent food intake, satiety and satiation.

Satiety and food intake are closely related to gastrointestinal transit and specifically gastric emptying. High-fat (HF) meals empty more slowly from the stomach yet are less satiating than isoenergetic low-fat (LF) meals. The current study examines how gastric emptying and satiety at lunch are affected by energy and macronutrient content of breakfast. Nine male volunteers consumed either (1) a HF breakfast, (2) a LF breakfast isoenergetic to HF (LFE) or (3) a LF breakfast of equal mass to HF (LFM). Gastric emptying half time measured using the sodium [(13)C] acetate breath test was delayed after HF compared to LF meals (HF: 102 + or - 11, LFE: 96 + or - 13, LFM: 95 + or - 13 min, mean + or - SD). Fullness increased and desire to eat decreased following the LFE breakfast measured using visual analogue scales. Eating a HF breakfast increased the energy, fat and protein from an ad libitum buffet meal given 4h after lunch. In conclusion, eating a HF breakfast delayed gastric emptying of lunch and increased food intake 7 h later compared to a LFM breakfast. These data suggest both mass and energy content of food regulate subsequent appetite and feeding and demonstrate the hyperphagic effect of a single HF meal.