Everything to Know About Serotonin

Serotonin is a substance in your body that helps nerve cells communicate with one another. Serotonin is mainly found in your gut, brain, spinal cord, and platelets (a type of blood cell that helps your blood to clot).

Some main roles of serotonin are to control behavior, mood, and memory. Increasing or decreasing levels of the substance can affect your health. For instance, low levels of serotonin in the brain and depression are believed to be connected. As such, serotonin level is a factor healthcare providers zero in on when treating mental health conditions like depression and anxiety. Meanwhile, high levels of serotonin can pose a different set of health risks. Healthcare providers can gauge whether your levels are optimal.

What Does Serotonin Do?

Serotonin performs a variety of functions in our body. That's all thanks to the many roles serotonin plays. Serotonin acts as a hormone and neurotransmitter, in that it helps cells communicate with each other. Serotonin also acts as a mitogen, meaning it gets your body's cells to start dividing. Serotonin also acts as a vasoconstrictor, causing your blood vessels to narrow.

The following are some of the main functions of serotonin:

• Regulates bowel function: When your gut cells sense food in your digestive tract, the cells release serotonin to keep the digestive process moving. Serotonin is also behind the development of nausea. If serotonin is released faster than it can be absorbed, you might feel nauseous.
• Controls appetite: As you eat, serotonin will lower your appetite.
• Regulates mood: Serotonin increases nerve stimulation and electrical impulses, which can help improve mood and happiness and decrease anxiety.
• Helps heal wounds: When serotonin is released into the blood, platelets take it in. Serotonin can then aid in clotting blood and reducing blood flow.
• Regulates sleep, memory, and learning: Serotonin plays an important role in the central nervous system (brain and spinal cord) and the functions the system upkeeps.
• Influences sexual function: Serotonin affects your body's ability to respond to sex (sexual function) as well as your desire for sex (libido).
• Impacts bone density: Some research suggests that blood serotonin is linked to bone density, which is the amount of bone mineral in your bones.

A majority of serotonin is present in the gut, part of the reason the substance plays such an important role in the functioning of the gastrointestinal tract. Even though there is less of it in the central nervous system, serotonin is essential in regulating that system's functions too.

What Happens If You Don’t Have Enough Serotonin?

Low levels of serotonin have been linked with low mood and depression. Symptoms of depression include persistent, near-daily, life-interfering feelings of:

• Sadness
• Anxiousness
• Emptiness
• Hopelessness or pessimism
• Irritability, frustration, or restlessness
• Worthlessness
• Fatigue or decreased energy

How Can You Raise Serotonin Levels?

If a healthcare provider determines that you could benefit from an increase in serotonin, there are several ways you can approach raising your levels.

Exercise

It's believed that working out can boost serotonin levels. That's even truer if the type of exercise is something you actually enjoy doing, like biking or swimming. Some experts believe that regular exercise can be as effective a treatment method for mood disorders than antidepressants.

The connection between exercise and higher serotonin levels might play a part in why people with more active lifestyles tend to have less anxiety and depression than those who are inactive.

Get Sunlight

There appears to be a direct relationship between sunlight and serotonin production. Research has shown that as the length of daylight changes from season to season, so too do serotonin levels. Serotonin levels have been found to be highest in the summer and fall, when daylight hours are longer.

In a 2021 study of women aged 60 or older, getting more than two hours of sunlight a day was linked to significantly fewer symptoms of depression.

Make Dietary Changes

Researchers are trying to get a better understanding of how diet can affect serotonin levels, as it's been suggested that having a balanced diet can reduce the symptoms of depression.

Although certain fruits and vegetables have serotonin, it is difficult for dietary serotonin to have an impact on the brain. Researchers are actually instead looking to other dietary substances that help serotonin make its positive impact. For instance, food that has increased levels of tryptophan, the amino acids that help in the synthesis of serotonin, might be particularly important. Tryptophan-rich diets are often recommended to combat depression.

Foods high in tryptophan include:

• Cheese
• Chicken
• Egg whites
• Fish
• Milk
• Sunflower, pumpkin, and sesame seeds
• Peanuts
• Soy beans
• Turkey

Vitamin B6 is also very important in raising the levels of serotonin in your body as its involved in converting tryptophan to serotonin. Foods high in vitamin B6 include:

• Fish (tuna, salmon)
• Beef liver
• Chicken breast
• Potatoes and other starchy vegetables
• Non-citrus fruit (bananas and squash)

Take Medication

Selective serotonin reuptake inhibitors (SSRIs) are a class of drug that increases serotonin levels. SSRIs are the first-line treatment for moderate to severe anxiety disorders and depressive disorders.

Serotonin and norepinephrine reuptake inhibitors (SNRIs) are another class of drug that can increase serotonin levels and may be used to treat depression. But unlike SSRIs, SNRIs increase the levels of norepinephrine as well, a hormone and neurotransmitter.

A healthcare provider can determine if medication is right for you and, if so, which one would be most effective.

What Happens If You Have Too Much Serotonin?

Your serotonin levels can get too high if you take certain medications and have a drug reaction known as serotonin syndrome. You would most likely experience serotonin syndrome if you are taking two or more medications that affect serotonin levels—especially when you first start taking the medication or increase the dose.

The medications either cause too much serotonin to be released or for too much serotonin to stay in the brain. Medications like triptans (for migraine), SSRIs, and SNRIs can potentially lead to serotonin syndrome. Talk to your healthcare provider about any concerns you may have; don't stop taking your medications without consulting them. Street drugs like ecstasy and LSD have also been linked to the syndrome.

Symptoms of serotonin syndrome can start within minutes to hours of taking the medications. Signs of serotonin syndrome include:

• Diarrhea
• Abnormal eye movements
• Nausea or vomiting
• Fast heartbeat
• High blood pressure
• Hallucinations
• Increased body temperature
• Loss of coordination

When treated, you usually get better in less than a day. When not promptly treated, you can slowly get worse, eventually become severely ill, and potentially die.

Even with treatment, you might have permanent organ damage. For instance, serotonin syndrome can cause muscle spasms that result in muscle breakdown. When the products of muscle breakdown filter out through the kidneys, the kidney can be damaged.

A Quick Review

Serotonin is a substance that has multiple roles in our body, including helping your nerve cells communicate with each other. Serotonin plays a part in regulating mood, behavior, sexual function, and appetite. Because low serotonin levels are associated with depression, people with certain mental health conditions may be prescribed medications to increase their serotonin levels. High levels of serotonin can result in a serious medical condition called serotonin syndrome. If you are taking any medications that impact serotonin levels, talk to your healthcare provider if you have any concerns about the effects the drugs may have on your levels.