The essential amino acid tryptophan (TRP) is discussed as a potential protective factor for physical and mental health. Besides positive effects via the microbiota of the gut on many physiological processes, TRP is the precursor of the neurotransmitter serotonin (5-HT), thereby playing a role for affective disorders. The present study investigated the effects of a TRP-rich diet on depressiveness and on one of its endophenotypes, impaired social cognition, in a population based sample. N = 482 subjects participated in an online study, assessing the ability to properly recognize emotional states from the eye region of faces (Reading the Mind in the Eye Test, RMET) and asking for subjective ratings of condemnability in a moral judgment task. Moreover, the habitual TRP intake was measured. It was hypothesized that a low-TRP diet is associated with higher depressiveness and worse performance in the social cognition tasks. The main hypotheses could be supported. However, contrary to the expectations, the effect of TRP on social cognition was not mediated by depressiveness. Results show that a tryptophan-rich diet is a potential protective factor against depression and is positively related to functioning in social cognition.

中文翻译：

---

富含色氨酸的饮食与抑郁症呈负相关，与社会认知呈正相关

必需氨基酸色氨酸 (TRP) 被认为是身心健康的潜在保护因素。除了通过肠道微生物群对许多生理过程产生积极影响外，TRP 还是神经递质血清素 (5-HT) 的前体，从而在情感障碍中发挥作用。本研究在基于人群的样本中调查了富含 TRP 的饮食对抑郁症及其内表型之一、社会认知受损的影响。N = 482 名受试者参与了一项在线研究，评估从面部眼部区域正确识别情绪状态的能力（在眼部测试中阅读心智，RMET），并要求对道德判断任务中的可谴责性进行主观评价。此外，还测量了习惯性 TRP 摄入量。据推测，低 TRP 饮食与更高的抑郁症和更差的社会认知任务表现有关。可以支持主要假设。然而，与预期相反，TRP 对社会认知的影响并非由抑郁介导。结果表明，富含色氨酸的饮食是预防抑郁症的潜在保护因素，并且与社会认知功能呈正相关。