Serotonin is a major regulator of mood and depression risk . These are important, vital roles, to be sure. Your mood describes how you experience and interpret the world. If it’s consistently bad, you’regoing to have a rough time. Yet, serotonin is much more than the “feel-good hormone.” It also influences sexual desire and helps us remember. It’s the precursor to melatonin , the neurotransmitter that allows us to sleep.
Although we mainly think of serotonin as a neurotransmitter acting on the brain, our guts are the biggest producers of serotonin. About 90% of the serotonin in our bodies is produced in the gut , where it helps trigger the contractions that push food through the GI tract and initiates nausea and vomiting (when necessary). That’s not the focus of today’s post on brain serotonin boosters, but I thought you’d all find it interesting.
Okay, so how can someone with inadequate serotonin levels boost the available serotonin in their brains?
Eat Animal Protein
We often forget that “thoughts” and “feelings” aren’t just ephemera floating around inside our heads without a material representative. Every thought, feeling, emotion, or mood we experience is a physical thing made of matter. We don’t just “feel better.” To feel better, we manufacture serotonin using an amino acid called tryptophan as the precursor.
Whether it’s turkey, eggs, dairy, beef, lamb , chicken, or fish, animal protein is a reliable source of tryptophan. Studies show that whey protein  and egg protein  both acutely increase tryptophan availability in the brain.
Get Plenty of Natural Light
Sunlight is a direct trigger of serotonin synthesis. The brighter the sunlight, the higher the serotonin production . This may explain seasonal affective disorder, where depression spikes during colder, darker months. It may also explain why sun exposure increases cognitive function  in both depressed and healthy subjects, or why bright light exposure prevents bad moods  after tryptophan depletion.
Bright light doesn’t imply full blaring sunlight . Going outside on a cloudy, late autumn day will expose you to far more bright, natural light than you’ll experience sitting inside with the lights on. I’d guess the main reason winter is worse for serotonin is that people are less likely to go outside and brave the bad weather.
Get your light as early as possible. A 10-15 minute walk just after sunrise (no sunglasses; bathe in the light) sets the tone for the day.
Get Your Vitamin D
Vitamin D—which we synthesize from UVB exposure—allows the conversion of tryptophan into serotonin .
I recommend getting most of your vitamin D from the sun. It’s better regulated that way, and you get the added benefit of lots of natural light. If you need or want to supplement (probably a good idea for most people during the colder seasons when sun exposure is low), look for a high potency formula. Here’s what I take .
Not only does seafood provide ample amounts of the amino acid tryptophan, the long-chain omega-3 fatty acids  found in marine fat increase serotonin production in the brain and improve serotonin transport across neurons .
You might take cod liver oil  or eat the actual livers, as that provides both vitamin D (for increased tryptophan conversion) and long-chain omega-3s. However, a good daily dose of omega-3 supplementation through high potency, pharmaceutical-grade fish oil  works fine, too, for those who get ample vitamin D otherwise.
Don’t Avoid Carbs Entirely
Carbs spike insulin, which shuttles amino acids out of the blood and into cells. This leaves tryptophan as the dominant amino acid in the bloodstream, because it’s bound to albumin and inaccessible to insulin. When amino acids compete for conversion into neurotransmitters, tryptophan wins, and serotonin rises, because no one else shows up.
Many readers of this blog prefer lower-carb diets. I’m the same. If you feel like your serotonin levels need a boost, consider increasing carb  intake a little.
Turmeric has emerged in recent years as a powerful antidepressant , in many cases equalling or even surpassing the effects of prescription antidepressants. Turns out that turmeric (or curcumin, rather) increases brain serotonin  levels in a dose-dependent matter.
So maybe you need curcumin, the isolated polyphenol found in turmeric, to really affect depression. Maybe your chicken tikka masala isn’t replacing your SSRI. But absent outright depression or serotonin-based mood disorders, cooking with turmeric  should help regulate normal serotonin levels.
Exercise increases serotonin via two pathways. First, the activation of motor neurons increases the firing rate of serotonin neurons, thus boosting the synthesis and release of serotonin. Second, exercise consistently elevates tryptophan levels in the brain , even for hours after the session.
Generic alternative health gurus will tell you caffeine depletes serotonin. It sounds right, doesn’t it? What they won’t say is that caffeine has actually been shown to increase brain serotonin, at least in rats . It also makes the brain more sensitive to the effects of serotonin. Personally, I’m drinking my coffee.
Get a Massage
Conventional experts will say “massage just feels good.” Well, yeah. That’s the point. Getting a massage boosts serotonin by 28% .
Get Your Micronutrients
This should really be standard advice for any health issue. Many problems go away when we eat more micronutrients—vitamins, minerals, and phytonutrients—because micronutrients are essential to fundamental physiological processes and pathways. It’s a safe bet that all of us are at least mildly deficient in a handful of important nutrients—like B6, which regulates serotonin synthesis .
One study  found that a food-based multivitamin/multimineral supplement drink called Lavita increased tryptophan and serotonin levels in healthy subjects. While that product does purport to offer  a boost in many micronutrients, a solid Primal diet with quality meats and good, varied vegetable intake should provide the same nutrient base. Of course, many of us choose a comprehensive multivitamin/multimineral supplement  as well.
That’s what I have for today, folks. Thanks for stopping by. Share your thoughts and questions on the comment board, and have a good week.
This post was originally published in 2007. I’ve revised it substantially to reflect current research findings and scientific understanding.