Changes in rats' meal patterns as a function of the caloric density of the diet.

Rats in a laboratory foraging paradigm were offered each of four diets which differed in caloric density, and intakes, meal frequencies, meal sizes, and eating rates were monitored. The rats maintained a constant daily caloric intake by eating more frequent, larger meals of the lower density foods. However, caloric meal size was not regulated, and significant correlations between meal size and the length of the post-meal interval were rarely found. The 24-hour pattern of calorie intake was the same regardless of diet. Higher-calorie foods were consumed at a faster rate within meals than were lower-calorie foods. The feeding patterns observed suggest that caloric intake may be regulated over a time frame of several meals rather than on a meal-to-meal basis.