Can increasing fruit and vegetables be an effective treatment for depression?
Fruit and vegetables provide us with many essential vitamins
and minerals. They are also high in fibre, provide our body with free-radical
fighting antioxidants, and have anti-inflammatory effects. Fruit and vegetables
also have important effects on our gut health by increasing the diversity of
our gut bacteria.
Fruit and vegetables have far reaching health effects and
their increased consumption is associated with improvements in physical health
and a reduction in several medical diseases including cardiovascular disease, certain
cancers, digestive disorders, metabolic diseases, and autoimmune diseases.
There is also increasing research confirming a relationship between fruit and
vegetable consumption and mental health disorders such as depression. For example,
people with depression have a lower intake of fruit and vegetables; and a low
intake of fruit and vegetables increases the risk of experiencing depression
[1].
As an intervention for depression, the research is limited.
However, the studies conducted so far are positive. Results from these studies
are summarised below:
- Participants experienced mental health improvements at 8 weeks follow up after brief nutritional and behavioural counselling to increase fruit and vegetable consumption [2].
- Eating two kiwifruits every day for six weeks resulted in modest improvements in mood [3].
- Results from a study on university students showed that snacking on one piece of fruit (either an apple, large clementine, or banana) a day for 10 days resulted in reductions in fatigue and anxiety compared to daily snacking on chocolate wafers or potato chips [4].
- A 14-day fruit and vegetable intervention where participants were given two additional daily servings of fresh fruit and vegetables to consume on top of their normal diet experienced improvements in psychological well-being, demonstrated by increases in vitality, flourishing, and motivation. However, it seemed that providing fruit and vegetables is important as psychological improvements did not occur in participants who were sent text message reminders to increase fruit and vegetable consumption plus a voucher to purchase fruit and vegetables [5].
These initial studies are promising although future research
is required to confirm the mental health benefits of increasing fruit and
vegetable consumption in people with depression and other mental health
problems. However, given the strong safety profile associated with their
intake, it makes sense to recommend increasing their intake. By including
dietary interventions in addition to psychological, lifestyle, and nutraceutical/herbal
supplementation it is possible that greater mental health improvements will
occur.
References
- Liu X, et al. Fruit and vegetable consumption and the risk of depression: A meta-analysis. Nutrition. 2016 Mar;32(3):296-302. link to article
- Steptoe A, et al. Quality of life and self-rated health in relation to changes in fruit and vegetable intake and in plasma vitamins C and E in a randomised trial of behavioural and nutritional education counselling. British Journal of Nutrition. 2004 Jul 1; 92(01):177–84 link to article
- Carr A.C, et al. Mood improvement in young adult males following supplementation with gold kiwifruit, a high-vitamin C food. Journal of Nutritional Science. 2013; 2:e24. link to article
- Smith AP and Rogers R. Positive effects of a healthy snack (fruit) versus an unhealthy snack (chocolate/crisps) on subjective reports of mental and physical health: A preliminary intervention study. Frontiers in Nutrition. 2014; 1. link to article
- Connor, T.S., et al. Let them eat fruit! The effect of fruit and vegetable consumption on psychological well-being in young adults: A randomized controlled trial. PLoS One. 2017; 12(2): e0171206. link to article
