{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,25]],"date-time":"2026-10-25T19:30:16Z","timestamp":1792956616068,"version":"4.5.0"},"reference-count":48,"publisher":"Cambridge University Press (CUP)","issue":"2","license":[{"start":{"date-parts":[[2015,1,9]],"date-time":"2015-01-09T00:00:00Z","timestamp":1420761600000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":["journals.cambridge.org"],"crossmark-restriction":true},"short-container-title":["Br J Nutr"],"published-print":{"date-parts":[[2015,1,28]]},"abstract":"<jats:p>Common pharmacological treatments of mood disorders aim to modulate serotonergic neurotransmission and enhance serotonin levels in the brain. Brain serotonin levels are dependent on the availability of its food-derived precursor essential amino acid tryptophan (Trp). We tested the hypothesis that delivery of Trp via food may serve as an alternative treatment, and examined the effects of a Trp-rich, bioavailable dietary supplement from egg protein hydrolysate on cognitive and emotional functions, mood state, and sleep quality. In a randomised, placebo-controlled, parallel trial, fifty-nine mentally and physically healthy women aged 45\u201365 years received placebo (<jats:italic>n<\/jats:italic> 30) or the supplement (<jats:italic>n<\/jats:italic> 29) (both as 0\u00b75\u00a0g twice per d) for 19\u00a0d. Emotional processing was significantly changed by supplementation, exhibiting a shift in bias away from negative stimuli. The results for the Affective Go\/No-Go Task exhibited a slowing of responses to negative words, suggesting reduced attention to negative emotional stimuli. The results for the Facial Emotional Expression Rating Task also supported a shift away from attention to negative emotions and a bias towards happiness. An increase in arousal-like symptoms, labelled \u2018high energy\u2019, shorter reaction times and a slight benefit to sustained attention were observed in the treated subjects. Finally, when the supplement was taken 60\u201390\u00a0min before bedtime, a feeling of happiness before going to bed was consistently reported. In summary, daily consumption of a low-dose supplement containing bioavailable Trp may have beneficial effects on emotional and cognitive functions.<\/jats:p>","DOI":"10.1017\/s0007114514003754","type":"journal-article","created":{"date-parts":[[2015,1,9]],"date-time":"2015-01-09T03:52:02Z","timestamp":1420775522000},"page":"350-365","update-policy":"https:\/\/doi.org\/10.1017\/policypage","source":"Crossref","is-referenced-by-count":66,"title":["Chronic treatment with a tryptophan-rich protein hydrolysate improves emotional processing, mental energy levels and reaction time in middle-aged women"],"prefix":"10.1017","volume":"113","author":[{"given":"M. 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