Macronutrient relationships with meal patterns and mood in the spontaneous feeding behavior of humans.

The role of protein, carbohydrate and fat ingestion on self-rated mood and subsequent food intake was investigated using self-reports of spontaneous food intake. Eight male and 30 female undergraduate students were instructed to list everything they ate, when they ate it, and their mood at the time of ingestion. They were asked to make these entries in a diary throughout a nine day period. Mood was rated at the beginning of each meal on three seven point scales; elated-depressed, tired-energetic, and anxious-tranquil. The amount of protein, carbohydrate, and fat as well as the total amount of food energy in each meal and the intermeal intervals (IMIs) prior to and following the meals were calculated with a computerized analysis. The energy content and the amount of each of the macronutrients contained in the stomach at the beginning and end of each meal was estimated with a mathematical model. These data were then intercorrelated using bivariate and multivariate techniques. Momentary self-rated mood was not found to be related to prior macronutrient intake nor was it predictive of subsequent intake. Long term macronutrient intake, averaged over the nine recording days, was found to be related to the averaged mood of the subjects. Although no significant relationships were found between the absolute amounts of the macronutrients ingested and mood, significant correlations were found between the proportion of each macronutrient in the diet and the overall self-rated mood.(ABSTRACT TRUNCATED AT 250 WORDS)