Eating over eight serves of raw fruit and vegetable may be associated with an increase in depression and poor feelings of well-being
A recent study involving 160,257 people conducted by the University of Alabama found that one out of three vegetarians have suffered from anxiety or depression in their lifetime.
According to the study, people on a plant-based diet were twice are more likely to take prescribed drugs for mental illness and three times more likely to consider suicide as compared to meat eaters
This systematic review of meat abstention and depression, anxiety and related phenomena’, evaluated that people who did not eat meat were at significant higher rates of depression, anxiety and self-harm.
Why does that happen?
Without meat, a vegetarian's diet tends to have less vitamin B12 and greater intake of omega 6 fatty acids (found n nuts), which has been linked with inflammation and increased risk of mental health problems (1)
However, a study published in Frontiers in Psychology, surveying more than 1100 young adults from New Zealand and the United States reported Well-being was highest in those who eat 4 to 5 servings of raw fruit and vegetables compared to those eating low levels less than 2 servings per day. But this advantage reduced to a lower feeling of well-being in those eating more than 8 servings daily (2)
Bottom line is, most people in Australia need to increase their intake of fruit and vegetables (3) however, these studies seem to conclude that extremely high intake over 8 serving daily may not be as healthy for our mental well-being as previously thought.
What diet may be best
As research is constantly reporting the Mediterranean diet seems to be associated with longevity and better mental, physical and cardiovascular health (4)(5)
Also, Adherence to a healthy Mediterranean Diet may exert beneficial effects in university students, promoting their academic performance and quality of life, as well as their mental and physical health status(6)
Urska Dobersek 1, Gabrielle Wy et al, Meat and mental health: a systematic review of meat abstention and depression, anxiety, and related phenomena. Crit Rev Food Sci Nutr. 2020 Apr 20;1-14
Shay-Ruby Wickham, Natasha A. Amarasekara et al, The Big Three Health Behaviors and Mental Health and Well-Being Among Young Adults: A Cross-Sectional Investigation of Sleep, Exercise, and Diet. Frontiers in Psychology, December 10 2020
Australian institute of Health and Welfair.Poor Diet 2020
Miguel-Angel Muñoz, Montserrat Fíto, et al, Adherence to the Mediterranean diet is associated with better mental and physical health, Cambridge University Press: 15 December 2008
Natalie Parletta, Dorota Zarnowiecki et al A Mediterranean-style dietary intervention supplemented with fish oil improves diet quality and mental health in people with depression: A randomized controlled trial (HELFIMED), Nutritional Neuroscience, Volume 22, 2019 - Issue 7
Marina Antonopoulou Maria Mantzorou et al, Evaluating Mediterranean diet adherence in university student populations: Does this dietary pattern affect students' academic performance and mental health? Int J of Health Planning and Management, Volume35, Issue1 January 2020 Pages 5-21