Updated: Jan 17, 2022
Over the past decade, numerous studies have been conducted examining the link between diet and mental health, including cross-sectional studies and longitudinal studies. Cross-sectional studies examine a sample of a population at a certain time, providing a ‘snapshot’ of the link between diet and mental health at a particular point in time. On the other hand, longitudinal studies follow a group of participants over time, examining any observable changes in the link between diet and mental health. A 2016 study by Rucklidge & Kaplan has synthesized the field of literature exploring nutrition and mental health into a systematic review. This review has gone over multiple studies, including cross-sectional and longitudinal studies, picking out the strongest supported conclusions and findings, and synthesized it into a single study.
In the systematic review, Rucklidge & Kaplan reviewed five studies showing that a ‘Western diet’ of highly processed foods high in sodium and saturated fat increases one’s risk for developing depression and anxiety. On the other hand, a Mediterranean diet rich in fruits and vegetables, healthy fats, nuts, fish, and low in processed food, decreases one’s risks for the development of said mental disorders. In these studies, the diet is shown to precede any observed changes in mental health, supporting a cause-effect relationship between diet and mental health.
The Mediterranean diet and lifestyle reflect the typical diet and lifestyle of someone living in countries like Italy and Greece in the 1960s, before the rise and global spread of the Western diet. However, there may be other factors aside from diet influencing observed mental health changes. In the Mediterranean lifestyle, diet, physical activity, and social activity was measured, which when taken together, is shown to cause a 50% reduction in risk of depression.
This may be due to the fact that the ‘Western diet’ is lower in essential vitamins and minerals we need to thrive. Four studies have shown micronutrient treatment to alleviate symptoms of depression, anxiety, explosive rage, irritability, and attention problems. This is especially important for youth, as the earlier the nutritional intervention, the greater the effect of micronutrient therapy.
We often look to supplements and medications to heal us, but perhaps we should be looking toward diet and lifestyle management as preventative measures against depression and anxiety. Should healthcare professionals start prescribing a Mediterranean diet and lifestyle as opposed to medications?
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