The association between protein consumption from animal and plant sources with psychological distress in older people in the Mediterranean region

Nathan M. D'Cunha, Alexandra Foscolou, Stefanos Tyrovolas, Christina Chrysohoou, Loukianos Rallidis, Evangelos Polychronopoulos, Antonia Leda Matalas, Labros S. Sidossis, Nenad Naumovski, Demosthenes B. Panagiotakos

Research output: Journal article publicationJournal articleAcademic researchpeer-review


BACKGROUND: The potential for diet to prevent and treat mental health conditions is an exciting area of investigation; however, the impact of different protein sources on mental health outcomes is unclear. OBJECTIVE: To evaluate the association between dietary protein intake and psychological distress, in people aged >50 years of age, living in Greece. METHODS: A combined data set of older people living in the Athens metropolitan area and 20 Greek islands, from the ATTICA (n = 1,128) and MEDIS (n = 2,221) population-based cross-sectional studies was developed. Anthropometric, clinical and socio-demographic and lifestyle characteristics, and protein consumption (total, animal, plant) consumed based on validated FFQ, were derived through standard procedures and questionnaires. 'Psychological distress' (PDS) was assessed as a combined variable representing symptoms of depression and anxiety using Item Response Theory methodology and fitting a Graded Response Model. RESULTS: Animal protein, but not plant protein intake, was associated with higher PDS following adjustment for age, sex, education level, Mediterranean diet adherence and physical activity (b±SE: 0.399±0.090, p = 0.003). Following analysis by Mediterranean diet adherence level, among low adherers, animal protein intake was positively associated with PDS (b±SE: 1.119±0.174, p = 0.003), and no associations were observed in moderate or high adherence groupsin regards to plant protein intake and PDS. CONCLUSIONS: Animal protein intake is associated with PDS, suggesting a bi-directional relationship, which may be influenced by Mediterranean diet adherence.

Original languageEnglish
Pages (from-to)273-285
Number of pages13
JournalNutrition and Healthy Aging
Issue number4
Publication statusPublished - Nov 2020
Externally publishedYes


  • anxiety
  • depression
  • dietary proteins
  • meat
  • Mediterranean diet
  • mental health
  • vegetables

ASJC Scopus subject areas

  • Food Science
  • Medicine (miscellaneous)
  • Biochemistry
  • Nutrition and Dietetics

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