Objective: Assessment of a possible relationship between perception of satiety and diet-induced thermogenesis, with different macronutrient compositions, in a controlled situation over 24 h. Design: Two diets with different macronutrient compositions were offered to all subjects in randomized order. Setting: The study was executed in the respiration chambers at the department of Human Biology, Maastricht University. Subjects: Subjects were eight females, ages 23 ± 33 y, BMI 23 AE3 kgam 2 , recruited from University staff and students.Interventions: Subjects were fed in energy balance, with proteinacarbohydrateafat: 29a61a10 and 9a30a61 percentage of energy, with ®xed meal sizes and meal intervals, and a ®xed activity protocol, during 36 h experiments in a respiration chamber. The appetite pro®le was assessed by questionnaires during the day and during meals. Diet induced thermogenesis was determined as part of the energy expenditure. Results: Energy balance was almost complete, with non-signi®cant deviations. Diet-Induced-Thermogenesis (DIT) was 14.6 AE2.9%, on the high proteinacarbohydrate diet, and 10.5 AE3.8% on the high fat diet (P`0.01). With the high proteinahigh carbohydrate diet, satiety was higher during meals (P`0.001; P`0.05), as well as over 24 h (P`0.001), than with the high fat diet. Within one diet, 24 h DIT and satiety were correlated (r 0.6; P`0.05). The difference in DIT between the diets correlated with the differences in satiety (r 0.8; P`0.01). Conclusion: In lean women, satiety and DIT were synchronously higher with a high proteinahigh carbohydrate diet than with a high fat diet. Differences (due to the different macronutrient compositions) in DIT correlated with differences in satiety over 24 h.