There is considerable evidence that eating a healthy diet can help reduce the risk of certain diseases such as cancer, diabetes, and high blood pressure. A healthy diet can also benefit your heart, your kidneys, and even your brain. What you eat can also affect your mental health.

Depression is one of the most common brain conditions affecting millions of people worldwide. Depression is typically treated with talk therapy and, depending on the severity of symptoms, a prescription for antidepressant medication. Over the past several years, studies have shown that eating a healthy diet can also have a positive impact on depression.

How Nutrition and Depression Work in your Brain

Brain-derived neurotrophic factor (BDNF) is a chemical in your brain that helps new brain cells grow and survive. It also protects brain cells from damage. Simply put, BDNF is like fertilizer for your brain, helping the brain cells grow, make connections with each other, and thrive. People with depression have lower levels of BDNF in their brain.

BDNF and Inflammation

When your immune system responds to infection or injury, it creates inflammation in your body. When inflammation works right, it helps your body fight disease and heal from injury. Sometimes inflammation can occur in the body when there is no infection or injury present. High levels of inflammation can be part of what causes depression. Too much inflammation in the body decreases the BDNF levels in the brain, and it has also been linked to many chronic diseases such as heart disease, cancer, Alzheimer’s disease, and diabetes.

Your Diet, BDNF, and Inflammation

The typical American or “Western” diet is high in saturated fats (from beef, poultry with skin, butter, cream, full-fat dairy), trans fats (in fried foods, baked goods, chips), fast food, processed food, sweets, and desserts.

Diets high in saturated fats and refined sugars have been shown to decrease BDNF levels in the brain and increase the odds of developing depression. In addition, eating fast food and processed food increases inflammation in the body, contributing to depression, anxiety, and other chronic diseases.

The Benefits of a Mediterranean Diet

Eating a Mediterranean diet has not only been proven to reduce your risk of heart disease and cancer, but studies have also shown it is helpful in preventing depression. The “Seguimiento Universidad de Navarra/University of Navarra” (SUN) Project studied a group of Spanish university graduates to look at the link between following a Mediterranean dietary pattern and the frequency of depression. The results showed that those who more closely followed a Mediterranean diet had a reduced risk of depression.

A Mediterranean diet is a diet rich in:

• Fruits
• Green leafy vegetables
• Whole grains
• Extra virgin olive oil
• Beans
• Nuts
• Legumes
• Seeds
• Herbs and spices
• Fish and seafood
• A moderate amount of poultry, eggs, cheese, and yogurt
• A minimal amount of meats and sweets

Changing Your Diet

When you’re feeling depressed, it might seem overwhelming to be told you need to change your diet. Sometimes it’s easier to start by adding healthy foods to your diet rather than to eliminate the unhealthy foods. You can start slow by buying a fruit that you like and commit to eating it three times a day. For example, if you like apples, have an apple with lunch and dinner, and one as a snack. Once you master adding fruit to your diet, you can try adding a vegetable to lunch, dinner, or a snack. The goal is to continue to add healthy foods to your diet while eliminating the unhealthy processed and fast food.

Nuts have also been shown to raise BDNF levels in people with depression, so adding a serving of almonds or walnuts in place of chips or crackers can be helpful. A serving of nuts is a quarter cup, which is one small handful. Be sure to choose nuts that are raw or dry roasted, and not in roasted in oil. You will probably discover that the nuts keep you full for a longer period of time than the chips do.

Although eating a healthy diet doesn’t necessarily eliminate the need for medication to treat depression, it is possible that it can minimize the amount of medication you need as part of a more comprehensive program including self-care and talk therapy.