Caloric compensation for lunches varying in fat and carbohydrate content by humans in a residential laboratory

Two groups of three subjects participated in a residential study that assessed the effects of varying the macronutrient and caloric content of a required lunch meal on subsequent food choice and intake. Lunches contained 431 or 844 kcal, with the caloric differential created by manipulating the calories derived from either fat or carbohydrate (CHO). Each lunch condition (high-fat, high-CHO, low-fat, and low-CHO) was examined for 3 consecutive days. Subjects controlled their own patterns of food intake and could consume any item or number of items at any time during the day or night. There were no significant differences in total daily caloric intake across conditions, indicating that subjects compensated for the caloric content of the lunch regardless of the macronutrient content. Total daily caloric intake under the high-fat and high-CHO conditions was 2824 ± 151 (x̄ ± SEM) and 2988 ± 187 kcal, respectively, whereas intake under the low-fat and low-CHO conditions was 2700 ± 131 and 2890 ± 247 kcal, respectively.