Effects of protein and carbohydrate meals on mood and performance: interactions with sex and age.

Normal adult subjects (n = 184) consumed a high-protein or high-carbohydrate meal. Two hours later their mood and performance were tested. The effects of meal composition on mood were different for men and women, and for older and younger subjects. Females, but not males, reported greater sleepiness after a carbohydrate as opposed to a protein meal. Male subjects, but not females, reported greater calmness after a carbohydrate as opposed to a protein meal. Older subjects responded differently to meals depending upon the time of day when these were consumed. When meals were eaten for breakfast (but not for lunch) individuals 40 yr of age or older felt more tense and less calm after a protein than after a carbohydrate meal. Although older subjects reported subjective discomfort after a morning protein meal, they displayed objective performance impairments after a carbohydrate lunch. Subjects 40 yr of age or older were impaired on a test of sustained selective attention (dichotic shadowing) after consuming a high-carbohydrate lunch. The shadowing impairment after carbohydrate consumption was as pronounced without distraction as with distraction and resulted mostly from increased omission errors. Our findings suggest negative effects on concentration when older subjects consume a high-carbohydrate, low-protein lunch. These negative effects of carbohydrate consumption appear to arise predominantly from lapses of attention rather than from intrusion of distractors.

[1]  J. Brobeck,et al.  A Mechanism of Regulation of Food Intake * , 1953, The Yale journal of biology and medicine.

[2]  R. Wurtman,et al.  Brain Serotonin Content: Increase Following Ingestion of Carbohydrate Diet , 1971, Science.

[3]  A. Bond,et al.  The use of analogue scales in rating subjective feelings , 1974 .

[4]  L. Fisher,et al.  Effects of long-term corn consumption on brain serotonin and the response to electric shock , 1975, Science.

[5]  W. Dement,et al.  Quantification of sleepiness: a new approach. , 1973, Psychophysiology.

[6]  G. A. Miller,et al.  Verbal context and the recall of meaningful material. , 1950, The American journal of psychology.

[7]  Spinweber Cl.  Daytime effects of L-tryptophan [proceedings]. , 1981 .

[8]  K. D. Hamsher,et al.  The Reliability of Reaction Time Determinations , 1977, Cortex.

[9]  R. Wurtman,et al.  Precursor control of neurotransmitter synthesis. , 1980, Pharmacological reviews.

[10]  J. Russell.  Affective space is bipolar. , 1979 .

[11]  J. Morley,et al.  Short-term and repetitive administration of oral tryptophan in normal men. Effects on blood tryptophan, serotonin, and kynurenine concentrations. , 1981, Archives of general psychiatry.

[12]  R. Wurtman,et al.  Nutrition and the brain. , 1990, Scientific American.

[13]  M. Herbert,et al.  Factor analysis of analogue scales measuring subjective feelings before and after sleep. , 1976, The British journal of medical psychology.

[14]  D. B. Duncan.  MULTIPLE RANGE AND MULTIPLE F TESTS , 1955 .

[15]  P Peltzman,et al.  The cry of the human infant. , 1974, Scientific American.

[16]  Second Edition,et al.  Statistical Package for the Social Sciences , 1970 .

[17]  M. Freyd,et al.  The Graphic Rating Scale. , 1923 .

[18]  E. Hoddes,et al.  The history and use of the Stanford sleepiness scale , 1971 .

[19]  M. Lader,et al.  The acute effects of oral (--)-tryptophan in human subjects. , 1975, British journal of clinical pharmacology.