Food and Mood: Does diet affect depression?

Depression is a common mood disorder that affects about 5% of all adults. However, Service Members are more likely to experience depression than most, reporting rates at about 23% among active-duty Service Members and 20% among Veterans. While the causes of depression can be complex, research into the relationship between nutrition and mental health has grown in recent years. “Nutritional psychiatry” studies how food can be a tool for prevention and treatment of mood disorders such as depression. In a world that can sometimes feel out of control, food might be a controllable factor that can help you improve your mental wellbeing.

How does food impact mood?

What you eat might support your mood and depression in 2 ways: by reducing the frequency of depression and by decreasing the symptoms of depression. Other ways your diet can affect your mental health include:  

  • Inflammation. Inflammation is your body’s immune response to something that’s potentially harmful. While this is your body’s normal response to things such as germs or a cut on your finger, inflammation that lasts over long periods of time can be harmful. Chronic, low-grade inflammation can even affect your mental health and contribute to depression. Healthy diet habits that include unsaturated fats, fiber, fruit, and vegetables provide nutrients that can help reduce your body’s inflammatory response and can improve your depressive symptoms.
  • Oxidative stress. “Free radicals” are atoms in your body that are missing electrons and are unstable. Free radicals are “bad” because they can cause damage to tissues. This is called oxidative stress, and  depressed people show to have higher levels of it than others. “Antioxidants” are molecules that share electrons, which helps stabilize free radicals and lower oxidative stress. Eating foods high in antioxidants, such as fruits and vegetables, can help lower oxidative stress and can improve your depressive symptoms. 
  • Brain plasticity. Brain plasticity, also known as neuroplasticity, is the ability of your brain and its neurons to adapt. Problems with brain plasticity can contribute to mood disorders, including depression. Foods that are high in antioxidants and anti-inflammatory compounds, such as fruits and vegetables, help your body produce proteins that help neurons survive, adapt, and function. This helps improve brain plasticity and can improve your depressive symptoms.
  • Microbiota-gut-brain axis. The trillions of bacteria that live in your gut, known collectively as “gut microbiota,” support your health and digestion and can even affect your mental wellbeing. What you eat can influence your gut microbiota and improve your health and depression outcomes. Regularly eating fermented foods and plant-based foods that are high in fiber can help nourish healthy gut bacteria  so that you, and your gut bacteria, can thrive.

What steps can I take to support my mental health?

Even though nutrients such as B vitamins and omega-3 fatty acids are necessary for brain function, for most people, using supplements for nutrients is unlikely to improve depressive symptoms or mood unless they’ve been diagnosed with a particular nutrient deficiency. Instead, following a healthy "dietary lifestyle," such as the “Mediterranean diet,” may help with managing your depression. The traditional Mediterranean diet is characterized by a high intake of fruits, vegetables, whole grains, legumes, nuts, olive oil, lean protein, and seafood—and a low intake of red meat, dairy, saturated fat, and added sugar. But don’t worry, there’s no need to move to Spain to eat foods that support your mental health! Below are 5 steps to incorporate the Mediterranean diet into everyday life—no matter where you live.

  • Swap saturated fats for unsaturated fats. Easy swaps can include cooking with olive oil instead of butter, using olive-oil-based salad dressings, and exchanging buttered toast for avocado toast. 
  • Replace processed snacks with plant-based options. A handful of raw nuts with vegetable sticks and hummus can replace that afternoon bag of chips—and you still get the crunch factor.
  • Choose whole-grain starches. Check the ingredient list while shopping for carbohydrates such as bread, and ensure the word "whole grain” is the first ingredient. You can also experiment with other whole grains, such as bulgur, barley, farro, couscous, and whole-grain pasta. 
  • When choosing protein, eat “less” legs more often. Choose protein options with “less legs,” such as fish (0 legs) and chicken (2 legs) more often than red meat (4 legs). This method will guide you toward lean protein sources and limit saturated fat in your diet. 
  • Eat at least 3 natural colors at every meal. By prioritizing more color on your plate, you can increase your intake of fruits and vegetables. By increasing fruits and vegetables, you can increase your meals' nutrient density and antioxidant capacity. For example, instead of just choosing broccoli as a side dish, increase your meal’s nutrient density by adding carrots and red bell peppers to the mix, too. 

Depression is a major concern for active-duty Service Members and Veterans. Looking at your individual and your group dietary patterns might provide substantial improvement of depressive symptoms and overall wellbeing.

Published on: July 3, 2024


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