The behavioral effects of food constituents: strategies used in studies of amino acids, protein, carbohydrate and caffeine.

Abstract

Summary Detecting the effects of foods and food con- stituents on behavior is difficult, due in part to the subtlety of the effects and the lack of stan- dardized and sensitive tests of human mood and performance. As more studies are con- ducted by different groups of investigators, however, it will become apparent that certain tests are more sensitive and that certain ef- fects are reliably present after specific foods are administered. For example, of the various tests that have been used, Simple Auditory Reaction Time has often been sensitive to the effects of foods and food constituents. Vigi- lance tests, particularly the version of the Wil- kinson Auditory Vigilance task we have used, also detect relatively subtle changes in behav- ior. Apparently minor details of these tests, including many histological or biochemical pro- cedures, may be critical in determining their sensitivity. In any case, it is certainly appro- priate to include a variety of tests in any behav- ioral study of foods. With regard to the other side of the equation, i.e., what foods to test, progress also is being made. It seems certain that tryptophan has sedative-like proper- ties,lslosl and carbohydrate foods relative to protein foods also may have similar effects.