What is Serotonin and What Does It Do?
Serotonin, also known as 5-HT, is a neurotransmitter released by the pineal gland of the brain. However, it has an effect on the entire body.
Serotonin and Mood
Serotonin is best known for its positive effect on mood.
It is believed that low levels of serotonin are associated with depression. This is called the serotonin hypothesis. In support of this theory, the most popular antidepressants are those that increase levels of serotonin. They are known as selective serotonin reuptake inhibitors or SSRIs. Unfortunately, these drugs are only effective in about half of patients.
There have also been studies demonstrating that tryptophan depletion may result in lowered mood and irritability. Since tryptophan is a precursor of serotonin, this suggests that low levels of serotonin are associated with lowered mood, irritability and even aggressiveness.
Clearly, more research is needed in this area, but we do know that low levels of serotonin are only part of the explanation for depression.
Serotonin and Cognition
Serotonin has an effect on other areas besides mood too. Serotonin receptors are also found in the brain regions involved in learning and memory. Studies have found that serotonin agonists (which lead to an increase in serotonin) prevent memory impairments.
Serotonin and Gastrointestinal Regulation
The majority of serotonin travels to the lining of the intestines and stomach. When we eat, serotonin is released and controls the contractions that push food through the digestive tract. An imbalance of serotonin has been linked to constipation, irritable bowel syndrome (IBS) and diarrhea.
Serotonin and Sleep
Serotonin plays an important role in controlling our circadian rhythms – our body’s internal clock. Serotonin levels are lowest while we’re sleeping and increase when we wake. It is believed that serotonin suppresses REM sleep and complements noradrenaline during wake.
Low serotonin may result in disrupted sleep.
Serotonin has also been implicated in:
- Heart rate regulation
- Blood clotting
Foods that Boost Serotonin
Many people would love to improve their mood and sleep without taking SSRIs or sleeping pills. This is understandable since both types of drugs have unwanted side effects.
So, people often turn to their diet to provide serotonin or its precursor, tryptophan. There are a few foods that contain serotonin or tryptophan.
Top 7 Foods That Boost Serotonin
Butternuts—a relative of walnuts— contain 398 microgram of serotonin per gram. Other nuts, such as walnuts, also contain serotonin.
Not only are pineapples delicious, but they’re really good for you too. Pineapples contain 17 micrograms of serotonin per gram. Not only that, but they also contain bromelain, which is an anti-inflammatory enzyme.
3.Bananas and plantain
You are probably more familiar with bananas than their family member, plantains. Plantains actually contain nearly double the amount of serotonin compared to bananas. While bananascontain about 15 micrograms of serotonin per gram, plantains contain about 30 micrograms.
Plantains shouldn’t be eaten raw like a banana. They should be cooked—preferably boiled or even fried.
Kiwis contain many antioxidants, along with about six micrograms of serotonin per gram. One study showed that kiwi consumption helped adults to sleep faster, longer and better.
Plums contain about five micrograms of serotonin per gram. Plums are also a good source of vitamin C, which is an immune system booster.
Vegetables typically contain less serotonin than fruits, but tomatoes have one of the highest levels among vegetables (they are technically fruits after all). There are about 220 milligrams of serotonin in a gram of tomatoes.
There might be a reason we reach for chocolate when we’re sad—chocolate does have an effect on serotonin levels. To get the highest benefit, you should look for chocolate with a high cocoa content.
Dark chocolate typically contains a high cocoa content (30 to 85%). Those with 85% cocoa have the most serotonin (2.9 micrograms per gram) and those with 70 to 85% cocoa have the most tryptophan (13.3 micrograms per gram).
Chocolate also contributes to an increase in serotonin because it contains carbohydrates (keep reading to find out more about this).
If you’d like an even healthier alternative to dark chocolate, try cacao nibs.