The Effects of a Mediterranean Diet on Symptoms of Depression in Young Men

Abstract

Background & Aims: The emerging field of nutritional psychiatry is a promising new area of research which examines the role of nutrition in mental health conditions. Yet despite the growing number of studies assessing the role of diet for depression, no research has explored the effect of diet in depressed young men (aged 18-25). This thesis addresses this research gap.  

Methods: This thesis includes four main research projects. First, a systematic literature review assessing the role of polyphenols on depression. Secondly, a cross-sectional online questionnaire which assessed the diets and nutritional knowledge of 384 young men with depression via the Men’s Diet and Depression Survey (the MENDDS study). Thirdly, a randomised control trial (RCT) which assessed a dietary intervention on the symptoms of depression in young men with moderate to severe clinical depression. A Mediterranean Diet for Men with Depression (the AMMEND study) assessed the effect of a 12-week Mediterranean diet verses a befriending control group. Lastly, a follow-up cross-sectional survey examining the experiences of the participants who completed the MD arm of the AMMEND study. 

Results: The results from the literature review reveals that the polyphenols found within a MD appear beneficial for depression. The MENDDS study found that the current dietary patterns of young men with depression are poor. Their diets are high in processed foods and low in vegetables and wholegrains. They believe their diet has an impact on their mental health and would be willing to change it to help improve their depressive symptoms. The AMMEND study found that young men with depression and poor diets are capable of significantly improving their diets over 12 weeks under the guidance of a clinical nutritionist. These diet changes led to improvements in depressive symptoms and quality of life. The AMMEND end-of-trial evaluation found the main challenges to include increased cost and time commitment, and the negative attitudes of friends/family to the diet.  

Conclusions: It is evident that diet appears to play a significant role in the mental health of young men. Based on these results, implementing a MD should be considered in the treatment of depression in young men, and referrals to nutritionists or dietitians should become routine. Additionally, by understanding the diet quality, nutrition knowledge, and barriers faced by young men, clinicians can tailor their dietary advice resulting in better outcomes. Further research is needed to determine the long-term effects of a MD in this demographic.