Research found that walnut consumption may improve mood in men. The research showed that non-depressed healthy, young males (ages 18-25) had a 27% reduction in overall mood disturbances after eating 2 ounces of walnuts every day for 8 weeks.1
While maintaining their typical diet, activities and lifestyle habits, 64 men and women consumed half a cup of walnuts daily by eating three slices of banana bread for about four months, half the time eating bread that contained walnuts and half without. Finely ground walnuts were added to the batter so there were no noticeable differences between the two types of banana bread. At the onset and after each phase of the study, participants answered a common questionnaire (Profiles of Mood States (POMS)) about key mood domains such as tension, depression, anger, vigor, fatigue and confusion. No significant changes in mood were observed in females or when the data was analyzed with both genders included. The greatest change among men that contributed to the reduction in mood disturbances was a 31% decrease in the anger-hostility domain.
Researchers believe the improvement may have been due to the unique nutrient profile from walnuts specifically the alpha-linolenic acid (ALA) content. Walnuts are the champion of ALA, the plant-based omega-3 fatty acid, offering 2.5 grams per ounce (approx. one-quarter cup).
Larger and longer-term studies are needed to clarify the benefits, especially in other populations. Additionally, more clinical trials are needed to determine the optimal quantity of walnuts needed to improve mood.
1Pribis P. Effects of Walnut Consumption on Mood in Young Adults – A Randomized Controlled Trial. Nutrients. 2016;8(11):668.