We’ve all heard serotonin called the “happy hormone”. While it’s not the only thing that affects our mood, it certainly plays a big role in how we feel. But there’s something many of us don’t realise: the food on our plate can affect how much serotonin our body makes.
Some foods can give your serotonin levels a boost, while others may actually bring them down over time.
In this blog, we’ll explore what serotonin is, what it does, how it’s produced in your body, and what are the foods that decrease serotonin levels. Let’s break it all down.
What is Serotonin?
Serotonin is a neurotransmitter (chemical messenger). It helps send the signals between your brain and nerve cells. It also regulates functions in our brain and bodies—including mood, sleep, memory, cognitive health, digestion, and many more.
That’s why having healthy levels of serotonin is important to feel balanced and well.
What Does Serotonin Do?
Serotonin is the key player in keeping your body and mind in balance. It’s involved in many important functions, most of which centre around maintaining homeostasis—your body’s natural state of stability.
Its specific roles can vary depending upon where it’s produced. But some of the key functions include:
- Mood Regulation—often called the “feel good” hormone, serotonin helps you feel calm, happy, and emotionally steady. Low levels of serotonin are often linked with mood disorders like depression
- Body temperature control—serotonin works with your hypothalamus to help keep your body temperature in check along with other homeostatic processes
- Supports cognitive functions—it influences how quickly you learn and how well you remember things
- Helps in wound healing—your blood platelets use serotonin to speed up the wound healing
- Helps in digestion and bowel movements—almost 90% of serotonin is produced in the GI tract where it helps regulate bowel functions and protect your gut. If you eat something harmful, your gut can release extra serotonin to speed up digestion and remove it from your body
- Appetite control—serotonin helps regulate how much you eat
- Bone health—serotonin may also affect bone density
- Sleep cycle—along with dopamine, cortisol, and melatonin, serotonin plays a key role in managing your sleep-wake cycle
- Sexual health—working with dopamine, serotonin can also affect sexual desire
In short, serotonin isn’t just about mood, it’s a multitasker which affects nearly every aspect of your well-being.
How is Serotonin Produced?
Your brain and gut make serotonin in the same way—and it all starts with an essential amino acid called tryptophan. As your body can’t produce tryptophan on its own, you need to get it from the food you eat.
After you eat, the tryptophan enters your bloodstream and travels to different parts of your body. With the help of certain vitamins and minerals like iron, vitamin B12, and folate it’s converted into serotonin in a series of steps.
What are the Foods that May Decrease Serotonin Levels?
Eating certain foods too often can affect your brain chemistry and may lower your serotonin levels. Here are 5 of them to watch out for:
1. Alcohol:
Alcohol is actually a central nervous system depressant which means it slows down your brain and central nervous system.
In small amounts, alcohol can give you that light, relaxed feeling that many people enjoy—because it triggers a short-lived boost in serotonin levels.
However, the effects change when you drink alcohol too much or too often. Regular use of alcohol can disrupt serotonin pathways , slowing down its production as well as breakdown in the brain.
Over time, this can lower overall serotonin levels and affect how well it works.
2. Caffeine:
Like alcohol, caffeine also affects the central nervous system—but instead of being a depressant, it acts as a stimulant. It increases brain activity and makes you feel more energised.
This boost causes a brief lift in serotonin levels, but caffeine also raises stress hormones like adrenaline and cortisol. Since serotonin helps calm the body, higher stress hormones mean your body needs even more serotonin to maintain the balance.
Drinking too much caffeine can cause other issues as well. It may reduce the absorption of iron in your body and lower vitamin B12 levels—both of which are essential for making serotonin.
3. Aspartame:
Aspartame is an artificial sweetener that is added to foods and drinks as a low-calorie alternative to sugar. While it does provide sweetness without extra calories, it comes with potential downsides.
Aspartame contains an amino acid—known as phenylalanine—in high amounts. Phenylalanine contains another amino acid—tyrosine—that is involved in making different neurotransmitters.
However, the problem is that tyrosine competes with tryptophan—the amino acid your body needs to make serotonin. When tyrosine wins that competition, less tryptophan reaches your brain, which may reduce serotonin production over time.
If your body is short on these nutrients, it’s harder to produce enough serotonin to keep up with the extra demand.
4. Fructose:
Fructose is a natural sugar found in fruits and vegetables. It’s generally considered a better option as compared to regular table sugar. But as with many things, too much can cause trouble.
For most people fructose can easily be broken down into glucose (blood sugar) and doesn’t cause any issues.
However, many people in Western countries have fructose malabsorption. The undigested fructose ends up fermenting in lower intestines causing symptoms like irritable bowel syndrome (IBS).
On top of that, unabsorbed fructose can also block the absorption of tryptophan—the key building block for serotonin. Without enough tryptophan, serotonin production can drop, leading to lower levels over time.
5. Trans Fats:
Fat is an important macronutrient playing a role in many things from energy storage to hormone production. But not all fats are equal—some are “good” for you while others can do more harm than good and are considered “bad”.
Trans fats fall in the category of “bad”. They offer little nutritional value and are linked to health problems like high cholesterol.
Eating too much trans fat can lower serotonin production, which is why diets high in trans fats are often linked with greater risk of depression.
They can also increase inflammation in the brain that can disrupt the production of “omega-3 fatty acids” which are one of the “good” or “healthy” fats.
Trans fats are most often found in processed, packaged, fried, and fast foods. While many countries have reduced or banned the artificial trans fats, they can still appear in small amounts, so it’s worth checking the food label.
Final thoughts:
Your mood, sleep, and overall well-being is influenced a lot by what’s on your plate. By cutting back on foods that may lower serotonin levels and making room for nutrient rich, balanced meals, you’re giving your body the tools it needs to keep you feeling steady and well.
And remeber—if you’ve been feeling persistently low, anxious, or irritable, it’s always best to talk to your doctor. Diet can play a big role, but sometimes we need a little extra support.
Learn here about when to seek help for anxiety.
