Restriction of meat, fish, and poultry in omnivores improves mood: a pilot randomized controlled study.

Vegetarian diets are associated with healthy mood states.

This pilot study investigated the effect of consuming diets that do not contain meat, fish, and poultry on mood states. 39 subjects participated in this study. They were assigned into 3 groups (fish, omnivore, and vegetarian groups) and placed on different diets for 2 weeks. The fish group was fed with fish 3-4 times per week, the omnivore group was given fish, meat, and poultry, and the vegetarian group was placed on a plant-based diet. Using the Depression Anxiety Stress Scale (DASS) and Profile of Mood State (POMS) questionnaires, researchers evaluated the mood states of all the subjects.

Researchers observed that members of the vegetarian group reported improved and better mood states than the other groups at the end of the dietary intervention. Low quantities of eicosapentanoic acid (EPA), docosahexanoic acid (DHA), and arachidonic acid (AA) and high concentrations of EPA and DHA were found in the diets of the vegetarian and fish groups respectively. The results of this study support the hypothesis that diets devoid of meat, fish, and poultry may improve mood states.