Does carbohydrate-rich, protein-poor food prevent a deterioration of mood and cognitive performance of stress-prone subjects when subjected to a stressful task?
This study investigates whether in stress-prone subjects, carbohydrate-rich, protein-poor food (CR/PP) prevents a deterioration of mood and performance under uncontrollable laboratory stress conditions. The assumption was that in stress-prone subjects there is a higher risk of serotonin deficiency in the brain and that carbohydrates may prevent a functional shortage of central serotonin during acute stress, due to their potentiating effect on brain tryptophan. Twenty-four subjects with a high stress-proneness (HS) and 24 subjects with a low stress-proneness (LS) participated in an uncontrollable stress situation under both a CR/PP and a protein-rich, carbohydrate-poor (PR/CP) diet condition. The plasma ratio of tryptophan to the other large neutral amino acids (LNAA) (ratio Tryptophan/ summation operatorLNAA) was determined as a measure indicating the dietary effect on brain tryptophan and serotonin levels. Significant increases were found in the ratio tryptophan/ summation operatorLNAA during the CR/PP diet compared with the PR/CP diet. Experimental stress had significant effects on pulse rate, skin conductance, cortisol and mood in all subjects. During the CR/PP diet only the HS subjects did not show the stress-induced rise in depression, decline in vigour and cortisol elevation that they showed after the PR/CP diet. With respect to cognitive performance, significant dietary effects were found on reaction time. It is suggested that CR/PP food in HS subjects may increase personal control, probably under the influence of higher levels of brain tryptophan and serotonin.
Department of Psychonomics, Utrecht University, The Netherlands.
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CR
Markus
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Panhuysen
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Tuiten
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Koppeschaar
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Fekkes
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Peters
D000293:Adolescent; D000328:Adult; D000339:Affect / Q000502:physiology*; D001923:Brain Chemistry; D003071:Cognition / Q000502:physiology*; D004032:Diet; D004040:Dietary Carbohydrates; D005260:Female; D006801:Humans; D008297:Male; D011930:Reaction Time; D012701:Serotonin / Q000032:analysis; D013315:Stress, Psychological; D014364:Tryptophan / Q000032:analysis
D004040:Dietary Carbohydrates; D012701:Serotonin; D014364:Tryptophan