How to Boost Serotonin

"I'm feeling so happy. It must be my serotonin," said no one ever. But it's true: serotonin, made from L-5-hydroxytryptophan (its precursor), is one of the "happy hormones" which deserves credit when you're enjoying that giddy sensation of feeling happy and emotionally balanced.

That's not all serotonin does; the serotonin molecule plays different roles throughout the body, supporting brain function and memory, a healthy stress response, sleep, and even your libido! So, if you've been feeling occasionally blue or have noticed some late-night disturbances, you may want to check your serotonin levels with a lab test. Low levels of serotonin can impact your mood and have been linked with mental health implications.

The good news is that you can promote your serotonin levels in healthy ways. How? Let's get started.

Does serotonin make you happy?

Absolutely. As a neurotransmitter, serotonin is associated with happiness, satisfaction, and optimism. Of course, the word "happy" is a bit subjective; sometimes we use this word to describe a feeling or mood, and other times, it can refer to our overall psychological state. That's because two underlying factors influence our experience of happiness: those that come from within (endogenic) and those outside of us (exogenic).

1. Endogenic factors

   —These are factors such as genetics, cognition, personality, and the biological processes that promote the production of chemical messengers like neurotransmitters (hello serotonin!) and hormones in the brain and body, making up the basis for happiness.

2. Exogenic factors

   —These are external factors such as behavior, culture, social engagement, geographical location, economic status, etc., that influence happiness.

So, while external factors may "rain on your parade," influencing how you feel, healthy serotonin levels are essential for a happy and balanced brain. While neither of these factors are completely within your control, the best way to boost your overall sense of well-being is to increase the things in your life that bring you joy, while also making lifestyle tweaks that support healthy serotonin production.

Is serotonin excitatory or inhibitory?

Your brain and body cells communicate with one another through chemical and electrical signals that carry excitatory (let's do this!) or inhibitory (stop!) messages—and serotonin can act as both! Depending on where in the body it's released, the serotonin molecule attaches to different serotonin receptors (in the brain, gut, or other organs outside the nervous system) to send its message.

The result? You feel emotionally balanced, have healthy sleep and wake patterns, food "moves along" your digestive tract, your romantic life is on point, and more!

Serotonin and gut bacteria

You may think that serotonin is produced in the brain, and you're not wrong, but about 90 percent of serotonin production takes place in the gut by intestinal cells. In fact, even your gut bacteria, the trillions of microorganisms that reside in your intestinal tract, can help support serotonin synthesis by your intestinal cells.

A large body of research shows there's a two-way highway between the intestinal tract and the brain. In other words, chemicals produced on either end travel along the gut-brain axis and affect one another—and serotonin function affects both how we feel and digestion. But the serotonin molecule can't cross the blood-brain barrier. That's why so much serotonin is produced in the gut (it can't get any from the brain), and it's anatomically separated from the serotonin produced in the brain.

Pro tip: Increase your intake of fermented foods and take a science-backed probiotic formula to promote better gut health.

So, to recap, serotonin is one of your happy hormones. Healthy serotonin levels are crucial for maintaining memory, mood, emotions, sleep, digestion, and other biological processes. Serotonin cannot cross the blood-brain barrier, so serotonin synthesis is significant in the gut.

How can I increase my serotonin levels?

Your body is an intricate composition of cells, tissue, organs and systems that work cohesively to support your overall well-being, and serotonin activity is an essential aspect of this process.

Building sustainable daily habits are healthy ways to boost and maintain serotonin levels. A great place to start is with the foods you choose; in addition, we'll discuss some serotonin supplements (well-known ones, like 5-HTP, and others that might surprise you), which can take over where your diet leaves off.

10 serotonin-boosting foods

Your body uses the amino acid tryptophan to make serotonin, and the foods you eat should be your primary source of tryptophan. Here are ten tryptophan-rich foods you can add to your meals.

1. Eggs

   —Scrambled or sunny side up, eggs are rich in tryptophan. Studies suggest that eggs can help boost tryptophan levels, which may help support healthy serotonin levels. Plus, eggs are a good source of vitamin D.

2. Cheese

   —If you're a cheese lover, we've got great news! Don't swear off that gooey goodness; it contains high levels of tryptophan. Which cheese to choose? Go for mozzarella, cheddar, or parmesan, they've been shown to provide a fair amount of this amino acid.

3. Pineapples

   —The tropical fruit is a well-known source of serotonin. Can't eat pineapple on its own? Add this antioxidant-rich tropic treat to your protein smoothie to get the serotonin-friendly benefits.

4. Salmon

   —Healthy fats are terrific for brain (and whole-body) health. Salmon isn't just rich in omega-3 fatty acids, but it also contains tryptophan. And it's lean protein—so, it's a win-win!

5. Nuts and seeds

   —Nuts and seeds, such as pumpkin seeds, pistachios, and cashews, are also a great source of tryptophan. Mix them with berries (a great source of antioxidants) for a brain-power snack! Nuts are also a great source of omega-3 fatty acids, so go nuts for them!

6. Tofu

   —If soy is part of your meals, you're in luck! Increase your intake of tofu and other soy products, which are good sources of tryptophan.

7. Turkey

   —You know that sleepy feeling that comes after that Thanksgiving fowl? It's thanks to its high tryptophan content. But it doesn't have to be a holiday for you to get the tryptophan benefits. Add turkey to salads (which happens to also be a great way to increase the protein in your lunch) and have them with mashed sweet potatoes.

8. Milk

   —Whole milk is a rich tryptophan source. It provides 732 mg per quart. Even 2 percent milk, providing 551 mg per quart!

9. Canned tuna

   —Here’s another tryptophan-rich source. A can of tuna provides 472 mg of tryptophan!

10. Oats

    —Overnight oats never looked better! One cup of oats provides 365 mg of tryptophan, and this healthy carbohydrate offers you all-morning energy and increases your fiber intake, too!

Pro-tip: Help your body access and absorb tryptophan by combining these foods with carbohydrates—think turkey and butternut squash purée, or salmon and roasted potatoes.

Serotonin supplements: 5-HTP, SAMe and more

Complement your healthy eating with a strategic nutritional plan. Here are eight supplements that help promote serotonin levels.

1. Tryptophan

   —The essential amino acid L-tryptophan acts as a precursor of serotonin—and the good news is, you can supplement if you don't get a lot of this nutrient from your diet. A study of 11 trials found that supplementing with tryptophan supports happy feelings and a positive mood in healthy adults.

2. 5-HTP

   —Another popular supplement is 5-HTP, or 5-hydroxytryptophan. 5-HTP serves as a direct precursor for serotonin. People take 5-HTP to promote calmness and relaxation.

3. SAMe

   —S-adenosyl methionine, aka SAMe, has shown mood-enhancing properties. A 2020 study found that SAMe showed encouraging and positive results, suggesting SAMe supplementation may help support serotonin levels.

4. Probiotics

   —Several studies suggest that specific probiotic strains can help improve mood and support feelings of calmness—thank you, gut-mind connection! Plus, you get probiotic benefits, too.

5. L-theanine

   — A clinical trial found that L-theanine supplementation helped improve mood and a relaxed state of mind.

6. Magnesium

   —This essential mineral is famous for supporting memory and youthful cognitive function. Choosing an ultra-absorbable form of magnesium, or a slow release formula, can help your body make the most of this mineral. Research suggests that magnesium supplementation can help increase serotonin and improve mood.

7. B vitamins

   —B vitamins, particularly vitamin B6, are necessary for serotonin synthesis and may help support healthy serotonin levels.

8. Folic acid

   —Here's another B vitamin that plays a role in serotonin synthesis: folic acid. A recent clinical study found that high total intakes of folate and folic acid helped promote a better mood.

Pro tip: Before taking any vitamin or supplement, check with your healthcare provider if you are taking any medications to ensure there are no contraindications.

Activities to support serotonin

Choosing tryptophan-rich foods and complementing those choices with the right dietary supplement is one piece of the puzzle. Incorporating serotonin-boosting activities into your wellness routine brings it full circle. Don't know how? Here are a few ideas to increase those feel-good moments every day.

• Sweat sessions are great for serotonin

  —You know body movement offers whole-body health. But it's also terrific for your brain and serotonin levels. A large body of research shows that aerobic exercise, the kind that gets you breathing and sweating heavily, directly impact serotonin and other neurotransmitters levels. The best part? It just takes 30-minues a day, at least five days a week, to get those serotonin-boosting (and whole-body health) benefits. Pro-tip: Work with your body. Target and tone large muscle groups with resistance and weightlifting exercises twice a week.

• Laugh your way to healthy serotonin levels

  —Laughter is the best medicine, and for good reason! Studies show that laughter not only helps boost serotonin but it also supports a healthy stress response, relieves muscle tension, and supports overall mental health—it's great for mind, body, and soul.

• Spend more time in nature

  —There's a reason we feel more upbeat during summer months. Surrounding yourself in nature and enjoying the open sky does your serotonin levels—and body—good, impacting your overall mood and mental outlook. Plus, exposure to sunshine is a good way to support vitamin D levels, which can have a positive impact on everything from your mental health to your heart health.

Let's sum it up! Healthy serotonin levels start with daily habits that help you live a serotonin-friendly lifestyle. Choose tryptophan-rich foods, make time for regular exercise, prioritize restful sleep, and cultivate a "zen" mind state—together, these habits are the cornerstones to boosting and maintaining serotonin levels where you want them.

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