Serotonin is a naturally-occurring neurotransmitter (a type of chemical that sends messages between neurons in the brain). The body can make serotonin on its own, but sometimes not in the amount we need to function optimally.

You’ve probably heard about serotonin levels in relation to depression, as one of serotonin’s most important functions is balancing mood. In addition, the chemical contributes to an overall feeling of well-being, which is why several antidepressant medications are designed to increase levels of serotonin in the brain.

However, these medications aren’t the only source of serotonin. Many of the foods we eat naturally contain serotonin. Bananas are a prime example of nutritious food that may help promote the mood-boosting benefits of serotonin.

It’s an appealing idea—but is it based in fact?

Bananas: Serotonin Superfood?

While bananas contain serotonin, having one for a snack won’t immediately lift your spirits. Unlike other forms, the serotonin found in bananas doesn’t cross the blood-brain barrier (which means it can’t get into the brain to supplement the serotonin that's naturally produced by the body).

However, research indicates that bananas may play a more indirect role by shoring up the amount of serotonin the brain is able to produce. The body needs other nutrients to properly make and use serotonin, including vitamin B6, and bananas are an especially rich source of this vitamin.

If a diet inadequate in vitamin B6 is contributing to low levels of serotonin, dietary changes may help—but that doesn’t mean eating one banana a day will be enough to improve your mood.

For adults (ages 19-50), the Recommended Daily Allowance (RDA) of vitamin B6 is 1.3 milligrams (mg).

A single medium banana has 0.4 mg (about 20% of the RDA).

To get enough dietary vitamin B6 from bananas alone, you’d have to eat five a day (literally a whole bunch).

Bananas may not be a miracle mood-lifter, but that doesn’t mean they’re nutritionally worthless. For one, bananas are low in calories (on average around 105 calories) and contain virtually no fat.

According to the USDA, one medium banana (7 inches-7 7/8 inches long) has around 3.1 grams of fiber—12% of the recommended daily value.

Bananas are also a rich source of potassium, an electrolyte that supports cells in nerves as well as the heart and other muscles. Having too little potassium in your diet can contribute to a number of health problems, including high blood pressure (hypertension).

You'll also get a decent dose of immune-supporting vitamin C from bananas; around 17% of your daily value.

Other Foods to Lift Mood

If you’re not a fan of bananas, there are plenty of other foods rich in serotonin and vitamin B6 you can choose from.

For example, a cup of canned chickpeas has 1.1 mg of vitamin B6. You can also get the vitamin from several protein sources, including beef liver, yellowfin tuna, salmon, and chicken breast.

Carbohydrate sources of vitamin B6 include fortified cereals and potato. A cup of boiled spuds has as much vitamin B6 as a medium-sized banana.

Several B6-rich foods also contain serotonin, such as fish and poultry. Turkey also contains another key nutrient for mood: an amino acid called tryptophan.

Tryptophan is a precursor to serotonin produced in the brain (the body can’t make the neurotransmitter without it).

Another important compound, 5-Hydroxytryptophan (5-HTP), also uses tryptophan. If the body is making too little, 5-HTP can also be taken as a nutritional supplement.

Research has shown that when paired with antidepressants, the supplement may be able to help ease symptoms of depression (however, additional research and clinical trials are needed to strengthen these claims).

Along with bananas, turkey, and chickpeas, there are many other foods that are natural sources of serotonin, as well as the other key nutrients the body needs to produce the neurotransmitter, such as:

Oily, fatty, fish (such as tuna and mackerel)
Nuts and seeds (especially walnuts and flaxseed)
Beans (kidney, pinto, and black beans)
Fresh produce (leafy green vegetables like spinach or kale)
Probiotic/fermented foods (kefir, yogurt, and tofu)

While a nutritious and balanced diet is beneficial for your physical and mental health, there is no one “mood-lifting” food that can be “cure-all” for depression.

Diet may be one aspect of treating the condition and you may decide to change how you eat to help you better manage your symptoms. However, it’s best to ensure you have the support of your doctor, as well as others such as a registered dietician and therapist, to ensure that you all of your nutritional needs are being met.