On the heels of research showing junk food really is addictive comes increasing suggestion that such foods may also lead to a cascade of reactions in your brain that trigger depression.
The link is not yet proven, and there are certainly many underlying causes of depression, however what you eat has been clearly shown to impact both your physical and your mental health. Alongside studies showing a fast-food diet can lead to heart disease, obesity and diabetes are those showing it may also mess with your mood. For instance, as reported by BBC News:
- People who followed a traditional Mediterranean diet were about half as likely to develop depression as those eating junk food
- Over five years, people who regularly ate processed, high-fat and high-sugar foods were about 60 percent more likely to develop depression
- A diet rich in olive oil, leafy vegetables and wine reduced inflammation and lowered the risk of depression by 40 percent compared to a pro-inflammatory diet of processed grains, sugary drinks and red meat (inflammation has been highlighted as a potential trigger for depression)
The depression-junk food link is even receiving attention from the U.S. Department of Defense, which is funding a trial delivering nutrient-rich food to former soldiers to determine if it helps to reduce suicide rates. The European Union also began a mood-food project to determine how different nutrients affect your mind.
As mentioned, one avenue by which food likely impacts mood is via inflammation. People with depression tend to have more inflammatory cytokines in their blood, which are typically released during illness or injury (but are also sometimes released chronically due to poor lifestyle choices, stress, exposure to environmental pollution and more).
In one study, when volunteers were triggered to release cytokines in their bodies, they experienced symptoms of depression, including dips in mood, inability to feel pleasure, and feelings of disconnection and loneliness. The take-home message is that anything that might cause you chronic inflammation might also lead to poor mood … and this includes your diet. BBC News explained:
“ … we may need to think about depression in an entirely new light – as a disease of the body as well as the mind. If so, many more things, besides life’s stresses, could put us at risk. Poor general fitness, smoking, and alcoholism are all known to increase an inflammatory response.
And so, feasibly, could your diet: high fat and sugar levels – and the fatty tissue that results from it – are known to increase inflammation and oxidative stress.”
On the other hand, certain beneficial nutrients are known to reduce inflammation and boost your mood. So while serious depression should be treated by a professional, you also have within your power the ability to make positive eating choices that may help significantly improve your mood. This includes:
- Omega-3 fats found in wild-caught fish and fish oil
- Minerals like zinc and selenium
- Leafy green vegetables
- Green tea (which contains an amino acid called theanine, which promotes a state of deep relaxation)