What is serotonin?
Serotonin is a naturally-occurring neurotransmitter that carries signals between nerve cells. (1) Most people are probably aware of serotonin’s role in the nervous system, where it helps with mood regulation and memory.
What you may not know is that most of the serotonin in the body is found in the gut, not the brain. The intestines produce the vast majority of the body’s supply of the neurotransmitter and it is needed to promote healthy digestion. (1)
Elsewhere in the body, serotonin plays a role in sleep, bone health, blood clotting, sexual function, regulating anxiety, wound healing, stimulating nausea, and bowel function. (2)
Serotonin and mental health
As serotonin helps to regulate mood, it’s often called the body’s “feel-good” chemical. (1) The influence serotonin has on mood makes it one of several brain chemicals that are vital to your emotional sense of well-being.
Low levels of serotonin can increase your risk of developing depression and other mental health disorders, including anxiety, post-traumatic stress disorder, and obsessive-compulsive disorder. (3)
The connection between our mental health and what we eat
It’s no secret that diet plays a key role in health and well-being. But in recent years research is beginning to reveal how what we eat influences our emotional and mental health.
One reason why our diet influences our brains so strongly is that our gastrointestinal system (i.e. the gut) is closely linked to the brain, a phenomenon known as the gut-brain connection. (4)
The gut is home to trillions of live microbes that have numerous functions within the body, such as synthesizing neurotransmitters - like serotonin - that send chemical signals to the brain to regulate mood, emotions, and so much more.
While there is still more to uncover, research suggests that what we eat influences the health of our gut microbe population, which in turn affects levels of neurotransmitters and thus our mental and emotional health. (4)
Serotonin is made from the essential amino acid tryptophan, which must enter your body through your food intake. (2) It’s been established, those with mood disorders such as anxiety and depression, have low tryptophan levels. Furthermore, research has shown that following a low-tryptophan diet causes levels of serotonin in the brain to drop. (5)
Tryptophan supplements can help increase your levels of serotonin, but for a more natural approach, you could try eating more of the foods that contain high levels of this amino acid.
8 Foods that boost serotonin
Here are eight foods that boost serotonin levels in the body. (3,5,6)
- Salmon: The oily fish is rich in tryptophan and two portions a week should be enough to keep your levels within the normal range. Salmon is also a source of omega-3 fatty acids, which help support strong bones, eye health, brain function, and healthy skin. It provides plenty of vitamin D, which also plays a role in bone health, as well as maintaining strong teeth and healthy muscles.
- Turkey: There is a reason you feel so sleepy after your Thanksgiving dinner - the high levels of tryptophan found in the holiday meal favorite. Turkey is also a great source of protein, is rich in vitamins and minerals.
- Tofu: If you follow a vegetarian or vegan diet, tofu (and other soy products such as edamame, soy milk, and seitan), is rich in tryptophan, and an excellent source of protein. As tofu is calcium set, it also provides a calcium boost to help maintain healthy bones and teeth.
- Eggs: Research has shown that the protein in eggs can boost blood plasma levels of tryptophan. (7) If you make sure to keep the yolks, you’ll also benefit from high levels of: (7,8,9,10)
- Choline: A vital nutrient that plays a role in liver function, brain development, metabolism, and mood regulation.
- Tyrosine: An amino acid that is an essential component in several neurotransmitters including epinephrine and dopamine.
- Biotin: Also known as vitamin B7, biotin plays an important role in metabolism, as well as supporting healthy skin, hair, and nails.
- Omega-3 fatty acids: Linked to numerous health benefits to the body and brain including supporting heart health, fighting inflammation, and improving mental disorders.
- Milk and cheese: Milk and cheese are also great sources of protein and rich in tryptophan. Furthermore, they are an excellent source of calcium for supporting healthy bones.
- Spinach: Dark green, leafy vegetables, like spinach, are a source of tryptophan. Spinach is also an excellent source of iron, which helps in the production of red blood cells, as well as reducing the risk of developing anemia (iron deficiency), which can cause low energy and breathing difficulties. The benefits of spinach don’t end there. It’s packed full of vitamins and minerals, which may help improve blood glucose control, improve bone health, maintain eye health, and support heart health.
- Nuts and seeds: Nuts and seeds may not include as much tryptophan as poultry, eggs, or oily fish, but they’re a good source of tryptophan and protein if you’re a vegan or vegetarian. Nuts and seeds are also sources of antioxidants, vitamins, and fiber. Some suggestions to add to your diet include sunflower seeds, sesame seeds, peanuts (unsalted), and pumpkin seeds.
- Oats: A beneficial grain all around, oats are a gluten-free, tryptophan containing whole grain, and a great source of fiber, vitamins, minerals, and antioxidants, Additionally containing eight other essential amino acids. (11)
Additional ways to boost serotonin
Natural serotonin boosters
There are numerous natural ways to help boost your serotonin levels, including: (1,3,6)
- Probiotics: About 95% of the body’s serotonin is produced in the gut with the aid of the colonies of beneficial gut bacteria. Therefore, it’s no surprise that eating foods and beverages rich in probiotics (like kefir, kombucha, and kimchi) can help support the population of good bacteria, which in turn can positively influence serotonin production. Also, being mindful of one's intake of foods that have an adverse effect on gut bacteria, such as artificial sweeteners, trans fats, and highly processed foods, may help maintain serotonin levels.
- Adaptogenic herbs: Adaptogens are plant extracts that help maintain balance in the body. Adaptogenic herbs may help maintain hormone levels, aid the stress response, and have antidepressant effects. Although further studies are needed, several herbs have been linked with relieving the symptoms of depression including ginseng and ashwagandha.
- Exposure to sunlight: Just a short time in bright sunlight every day can have double the benefits to your serotonin levels. Bright light is known to promote serotonin production by stimulating the body’s circadian rhythm and by boosting vitamin D levels which play a role in the production and activation of serotonin. Special lamps are available to mimic exposure to sunlight in winter or when access to bright sunlight is limited.
- Move your body: It’s widely known that exercise is beneficial for mental health with research indicating that physical activity promotes the release of serotonin and other mood-boosting chemicals.
- Stress management: Sustained stress impairs the function of serotonin receptors and negatively impacts serotonin production. Therefore, stress management can help maintain optimal serotonin levels. Some evidence-backed stress management techniques include mindfulness, yoga, breathing exercises, and meditation.
Selective serotonin reuptake inhibitors (SSRIs) are a type of antidepressant that increase serotonin levels in the brain by blocking reabsorption of the neurotransmitter so more of it remains active in the body. Commonly prescribed SSRIs include Zoloft, Luvox, Celexa, and Prozac. (2)
Another group of serotonin-based medications used to treat depression is serotonin-norepinephrine reuptake inhibitors (SNRIs). They work in a similar fashion to SSRIs by blocking the reuptake of serotonin, but they also affect norepinephrine, another neurotransmitter involved in mood regulation. (1) Examples of SNRIs include Pristiq and Fetzima.
While not a replacement for medications prescribed by your doctor, some supplements may be able to boost your serotonin levels, including: (2)
- Tryptophan: As previously mentioned, tryptophan can be converted into serotonin in the brain, potentially raising serotonin levels. Research indicates tryptophan supplementation could reduce anxiety and improve mood.
- St. John’s wort: The natural supplement is derived from an herb and has been shown to increase serotonin levels in the body. While the findings of the research are not always consistent, St. John’s Wort may be beneficial for reducing the symptoms of depression.
- S-adenosyl-L-methionine (SAMe): This supplement is often advertised as an alternative treatment for depression, but more research is needed to further understand its effect on serotonin levels and mood.
It’s important to be aware that these supplements can increase your risk of serotonin syndrome, which occurs when the levels of serotonin in the brain are too high. Serotonin syndrome can range from mild (diarrhea and shivering) to severe (fever, muscle rigidity, and seizures). (12)
Therefore, if you are considering trying serotonin-boosting supplements, it’s important you speak to your healthcare team first, as certain supplements can’t be taken with certain medications.
If you’re in recovery…
If you’re in recovery from an eating disorder before you make any changes to your eating, medication, supplements, or movement, you should speak to your treatment team first. They will be able to help you to incorporate these new foods or supplements into your meal plans, ensuring they are still in line with your treatment plan.
They will also help suggest physical activities that work best for you, which is crucial if you’ve previously struggled with excessive exercise.
If you’re looking to boost your serotonin levels with the aim of improving your low mood or other symptoms of depression, please get in touch with your treatment team. Recovering your eating disorder is not the only goal of treatment, addressing all of your mental health is just as important to your team as treating your physical health.