Introduction and objective:
Among the factors influencing the development and inhibition of depression symptoms are food and nutrients. The aim of the study was analysis of depression symptoms among vegetarians and omnivores in Poland using BDI-II and assessment of the quality of their diet.

Material and methods:
The study involved women, 50 vegetarians and 50 omnivores, aged 17–50. BDI-II, author›s questionnaire and nutritional diary were used for the analysis.

Statistical analysis showed no significant relationship between the duration of the vegetarian diet and the occurrence of depression. There was no correlation between supplementation and the appearance or absence of depression symptoms. Vegetarians with symptoms of depression provided adequate amounts of magnesium. The results were statistically significant. Vitamin B12 deficiency was found in vegetarians with and without depressive symptoms (p>0.05). The consumption of omega-3 fatty acids, tyrosine and tryptophan was higher among non-depressives among vegetarians and omnivores. These results were not statistically significant. Vegetarians with symptoms of depression consume more alcohol (p>0.05). Vegetarians with symptoms of depression and omnivores without symptoms also consumed the most caffeine (p>0.05).

Depressive symptoms were more common among vegetarians. Analysis shows that it is impossible to find a nutritional cause that would have a significant impact on the development of depressive symptoms. In the studied group of vegetarians, nutrition was a insignificant factor in the presence or absence of depressive symptoms. Nevertheless, there is a need for additional research on the impact of a plantbased diet on the mental health of the vegetarian community, among both men and women.

With the exception of public resources from the Polish Ministry of Higher Education in Warsaw, Poland, no specific grant was received from funding agencies in the, commercial, or not-for-profit sectors.
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