The connection between food and depression is not fully understood, but there is enough research to suggest that focusing on certain ones may lessen one’s likelihood of developing depression or potentially aid in treating existing depression. Here are eight nutrient-rich foods that can help fight depression.

Oysters

Eating oysters to treat depression may sound odd, but a psychiatry professor at Columbia University recently made headlines by revealing he encourages patients with depression to regularly consume oysters. So exactly what’s in them that could potentially impact mood? Turns out that oysters, as well as other mollusks and shellfish, are a great source of zinc, which plays a key role indaily brain functioning—specifically in regard to mental clarity, behavior, and attention.

Research has also noted that those with depression tend to have lower levels of zinc. While it’s unclear if a lack of zinc leads to depression, or if low zinc levels are a side effect of depression, almost everyone can benefit by incorporating more zinc-rich foods. Oysters and other shellfish are good choices, since they also provide vitamin B12, omega-3 fatty acids, and selenium—three other nutrients also associated with brain health.

View Recipe: Roasted Oysters With Pancetta and Breadcrumbs

Wild Blueberries

All berries are great food choices, but blueberries rise to the top thanks to their high levels of Vitamin C and polyphenols. These compounds act as antioxidants protecting brain cells from harmful free radicals and promoting proper brain functioning, particularly during stressful periods. For an even bigger boost to brain health, opt for blueberries labeled “wild,” which are a specific type harvested in the Northeast that appear to have higher concentrations of the antioxidant-like compounds.

In fact, when given a drink made with wild blueberries, both kids and adults were reported to have a significant increase in overall mood and outlook two hours later. Most wild blueberries are frozen immediately after harvest to preserve nutrients, so look for them near other frozen berries and fruit. Then use just as you would other frozen fruits for smoothies, or thaw and stir into batter for muffins.

View Recipe: Milk Chocolate Yogurt With Granola and Blueberries

Fermented Foods

Research continues to suggest that gut bacteria plays a role in the development of a variety of mental health issues (including depression). While we don’t fully understand this connection, we do know that food can directly influence just how healthy and diverse those gut microbes are.

Most agree that adding food rich in good bacteria—such as fermented foodslike kimchi, kombucha, miso, tamari, tempeh, and sauerkraut, as well as fermented dairy products like yogurt—to your diet is beneficial to your overall health. In fact, a meta-analysis of almost 100 studies found that depression risk was reduced significantly by regularly consuming probiotic-rich foods.

View Recipe: Savory Broccoli-and-Sauerkraut Salad

Salmon

Salmon offers a two-pronged approach when it comes to fighting depression because it not only provides omega-3s that are essential to brain health, but it is also a source of Vitamin D. While the majority of the population may not be deficient in Vitamin D, data suggest that most aren’t consuming adequate amounts, which is noteworthy since lower blood levels of Vitamin D are associated with a greater risk of depression.

View Recipe: Salmon Croquettes With Yogurt-Dill Sauce

In addition, the omega-3 fatty acids in salmon and other fatty fish are DHA and EPA, both of which are directly linked to brain health. Primary sources of DHA and EPA are fish and sea plants like algae. Eggs and poultry also have small amounts, but other commonly recognized omega-3 foods, like nuts and seeds, don’t contain EPA and DHA. This means getting adequate amounts can easily get neglected without regular fish intake, so aim to eat a 4- to 6-ounce serving of fatty fish like salmon two to three times per week to load up on those brain-essential omega-3s and vitamin D.

Leafy Greens

Leafy greens rank as a top food when it comes to fighting depression, based on their high nutrient content. This is according to a recent study that examined the amounts of 12 nutrients, all specifically associated with mental health, in various foods. The top plant foods with the highest amounts of these nutrients were leafy greens, followed by peppers and cruciferous vegetables like broccoli, while the top animal foods were oysters and mussels.

Leafy greens like spinach, kale, collards, cabbage and watercress are high in Vitamin C, beta-carotene, and folate. Many feel getting adequate folate daily is key since a deficiency in folate is associated with a greater risk of depression. For optimal brain health, most recommendations suggest eating a serving of leafy greens daily (or around 5 to 7 cups per week).

View Recipe: Gnocchi With Spinach and Pepper Sauce

Walnuts

Walnuts are already a top nut for heart health, thanks to their powerful combo of omega-3s, vitamin E, and antioxidants, but they may also reduce your risk for depression. A study published earlier this year that analyzed data from over 26,000 U.S. adults found that those who regularly ate walnuts had a significantly reduced risk for depression. In fact, the study found that depression scores were 26% lower for individuals who ate approximately 1 ounce of walnuts each day and 8% lower in those who ate 1 ounce of another type of nut each day, when compared to others who didn’t regularly consume nuts.

View Recipe: Fig and Arugula Salad With Walnuts and Goat Cheese

Lean Proteins

Eating adequate protein isn’t just about maintaining muscles—not getting enough could potentially impact mental health. Research that suggests that low levels of B12, a vitamin predominantly found in animal protein sources, may put an individual at higher risk for suffering from depression.

The trick is to aim to get adequate protein each day from a variety of both animal and plant-based sources and to make sure the animal proteins you choose are from lean sources like fish, poultry, eggs, and lower-fat dairy. Getting adequate B12 can be a little trickier for vegetarians who eat few to no animal proteins. Fortified grain products are an alternative, but the vitamin may not be absorbed as well.

Another mood-boosting perk from lean protein foods like tuna, turkey, and beans is that they also contain the amino acid tryptophan. While often associated with sleepiness after eating Thanksgiving turkey, tryptophan is a precursor to serotonin, a key mood-boosting brain chemical.

View Recipe: Thai Turkey Lettuce Cups

Beans

Eating a high-fiber diet promotes a healthy digestive tract, but it may also make you less prone to depression. Research suggests that depression develops as a result of inflammation in the brain that triggers altered neurotransmitters and impaired brain functioning. But how does fiber come into play? Some strains of good bacteria use soluble fiber to produce short-chain fatty acids (SCFA) in the gut which have an anti-inflammatory effect.

All beans ranging from black beans to chickpeas are good soluble fiber sources. Other good sources include peas, lentils, fruits, and vegetables, so make sure to eat these foods every day for an added fiber boost.

The Bottom Line

While no food will magically cure depression, eating a healthier diet full of these foods may help improve physical and mental function. If you believe you have depression, or you’re struggling with your mental health, visit your doctor to find a treatment plan that's right for you.