Melatonin has an impressive resume. This hard-working hormone helps almost all the tissues and organs in your body do their jobs. (1)
Despite this, you may only think of melatonin for sleep. This is because that’s what tends to get the most press. The full story is that this hormone does so much more.
Melatonin may help protect you against allergies, support digestive health, aid detoxification, and fight parasites. Those are just a few of its many potential roles.
Fortunately, your body makes melatonin, which helps keep you supplied with this vital compound. Still, modern lifestyles can mess with your melatonin levels.
Here’s a closer look at melatonin’s functions in your body. You’ll also learn tips for supporting healthy melatonin levels.
How Melatonin Helps You Sleep
Most of the melatonin circulating in your blood is made in your pineal gland. This “melatonin factory” is about the size of a grain of rice and is located between the two halves of your brain.
Your pineal gland produces melatonin in sync with your internal “body clock,” which operates on a 24-hour cycle. (2)
Here’s how it works: Light receptors in your eye perceive the amount of light around you. Based on this, they send signals to your pineal gland to produce more or less melatonin.
As the sun sets, your melatonin level increases to promote rest. Your body starts to cool and slow down to prepare you for sleep. When your melatonin level drops with daylight, this helps wake and warm you up.
Unfortunately, modern lifestyles can reduce your melatonin production at night. Artificial light — particularly the blue light from smartphones and other digital devices — can trick your pineal gland into thinking it’s daytime all the time. (3)
Reducing your blue light exposure at night helps increase your melatonin level and promote sleep. That could have far-reaching benefits beyond feeling well-rested.
Your brain detoxifies during the night. It needs quality sleep to do that. Poor sleep is linked to lagging brain function and memory, especially as you age. (4, 5, 6)
Melatonin Aids Digestive Health
The pineal gland is only one part of your body that produces and secretes melatonin. Several areas of your digestive tract also release the hormone.
Melatonin is secreted by your: (7, 8)
- Salivary glands
- Stomach lining
- Intestinal lining
Research suggests that melatonin levels in your digestive tract may be 10 to 100 times higher than in your blood. (2)
Moreover, the concentration of gut melatonin is estimated to be 400 times more than in the pineal gland. (9)
What is melatonin doing in your gut? Read on to find out how it supports several aspects of digestive health.
Supports gut health and regularity
Melatonin is a powerful antioxidant and may help protect the lining of your digestive tract. This includes guarding against heartburn and ulcers. (8, 10, 11)
It may also help control pain in your digestive tract, such as may occur in irritable bowel syndrome (IBS) and ulcerative colitis. (12)
Additionally, melatonin supports regularity and steers you away from constipation and diarrhea. The hormone can nudge your gut motility in either direction, as needed. (13)
Still, sometimes you may need extra support for gut health. If you’re struggling with constipation, digestive herbs may help.
Supports gut microbiome health
Another important aspect of gut health is your microbiome. The trillions of bacteria and other microbes in your gut can affect digestive health, as well as your overall health. (14)
Studies suggest that both melatonin and TUDCA support a healthy microbiome. They promote greater diversity of beneficial gut bacteria. (15, 16, 17)
Melatonin also has antifungal actions in your gut, including against Candida albicans. Overgrowth of this yeast may be an underlying cause of many health issues. It promotes inflammation and can prevent cells from healing. (18, 19)
Candida can multiply unchecked in your gut when it hides in a blanket-like biofilm. Melatonin may prevent the yeast from forming a biofilm. This could reduce your risk of Candida overgrowth. (20)
Melatonin Supports Detox
Melatonin supports your detox organs. This includes your liver and kidneys. Here’s a closer look at how melatonin may help keep these organs healthy so they can do their jobs.
Melatonin and your liver
Your liver produces bile and releases it into your small intestine. Bile helps with fat digestion, but that’s not its only benefit.
Bile also helps you get rid of toxins. Examples are chemical pollutants, mycotoxins (from mold), medications, heavy metals, and alcohol. (21)
After your liver processes toxins filtered from your blood, it deposits some in your bile. In your gut, bile is caught up in your stools and “flushed away.”
This is a great system, but your liver has limits. What happens when it’s bombarded with toxins day in and day out?
Over time, your liver can sustain damage from processing high levels of toxins. Your liver cells may start to malfunction, and chronic liver disease can develop.
Melatonin could come to your aid in several ways. In your liver, it may help: (21, 22, 23, 24)
- Restore antioxidant activity
Protect membranes of cellular structures, including mitochondria
- Reduce inflammation
- Prevent premature cell death
- Prevent fibrosis (scarring)
These protective actions on your liver could help prevent toxins from building up.
Amino and bile acids support your liver when it’s challenged by toxins. Along with melatonin, they help your body maintain vital detox functions. (25)
For further detox support, consider taking binders. They can provide additional support to complement melatonin.
Melatonin and your kidneys
After your liver processes toxins, some are released into your blood. The kidneys filter these from your blood so you can excrete them in your urine.
But like your liver, your kidneys can become damaged when overexposed to harmful substances. That includes common ones like pesticides, dry cleaning chemicals, and heavy metals. This damage can result in reduced kidney function. (26, 27)
Animal tests suggest melatonin may help prevent damage to the kidneys. This may be due to the hormone’s antioxidant properties. (28)
Melatonin Helps Protect Brain Health
You already know the pineal gland in your brain produces melatonin. But, that’s just the beginning of the hormone’s connection with your mind.
Melatonin can pass through your blood-brain barrier. This is like a gatekeeper. It prevents direct access of materials from your blood into your brain. Melatonin is allowed to pass through because it helps protect your brain.
In fact, melatonin may shield your brain from both psychological and physical stressors. (29, 30)
In modern-day living, you may face mild, stressful situations on nearly a daily basis. Animal studies suggest melatonin reduces this kind of chronic, low-level psychological stress. (31)
What about physical stressors to your brain, like a stroke or brain disease?
Animal and lab studies suggest melatonin may inhibit brain damage in: (32, 33, 34)
- Alzheimer’s disease
- Parkinson’s disease
- Huntington’s disease
- Traumatic brain injury
- Amyotrophic lateral sclerosis (ALS)
The antioxidant properties of melatonin may help protect against damage in brain challenges. The hormone also provides anti-inflammatory protection to the brain. (35, 36)
Additionally, melatonin may protect your blood-brain barrier from damage. Preserving the barrier may help protect against cognitive decline in aging. (37)
Melatonin Fortifies Your Immune System
Melatonin may support your immune system in several ways. It may help protect you against allergies and autoimmune conditions. It may also bolster your immune system to fight parasitic infections.
Autoimmunity and allergies
Allergies and autoimmunity — two possible results of a dysfunctional immune system — are on the rise.
Autoimmune diseases are ones in which your immune system mistakenly attacks your healthy cells. Examples are rheumatoid arthritis and multiple sclerosis.
Could lifestyle habits that suppress melatonin levels — like being glued to your digital devices at night — be partly to blame for the rise in autoimmunity and allergies? It’s worth considering.
Studies suggest that if you have lower blood levels of melatonin, you may have an increased risk of allergic skin rashes and asthma. (38)
Melatonin is a small molecule that easily passes through your cell membranes. So, it can get inside your cells and provide antioxidant protection. That may help defend you against autoimmune conditions and allergies.
Additionally, animal studies suggest melatonin may help protect the thyroid gland from dysfunction. Autoimmune thyroid disease is the most common type of autoimmune condition. It’s also linked to allergies. (39, 40)
Your immune system is designed to help guard against pathogens, including parasites. These unwelcome critters can cause a range of symptoms. Food sensitivities, digestive issues, and brain fog are a few symptoms you may have.
Melatonin supports your immune system function. This may help you fight parasitic infections, as well as pathogenic and bacterial infections. (41)
In an animal study of Chagas’ disease — caused by the parasite Trypanosoma cruzi — melatonin helped decrease replication of the critter. Chagas’ disease has been reported in the southern United States, as well as Central and South America. (42, 43)
In other animal research, melatonin fortified the immune system to better fight Toxoplasma gondii. That’s a protozoan parasite you may get from undercooked meat, particularly lamb and pork. (44, 45)
For additional parasite defense, you can take herbs to help you purge the critters.
Melatonin Supports Your Heart, Blood Sugar, and Weight
Heart disease, type 2 diabetes, and obesity are often intertwined. Following a healthy lifestyle — including eating nutritious foods and exercising regularly — is crucial for reducing your risk of all these conditions.
Melatonin supports your efforts in keeping these health problems at bay.
For good health, you need well-controlled blood sugar. Insulin is the hormone that enables glucose (sugar) to enter your cells. This helps keep your blood sugar under control.
When your cells become less sensitive to insulin or you aren’t making enough insulin, you can develop type 2 diabetes.
Lab studies suggest melatonin may help reduce the loss of pancreatic cells that make insulin. What’s more, melatonin may help these cells function better. That would help keep your blood sugar in check. (46)
Melatonin could also indirectly reduce your risk of diabetes. It may do this by promoting a healthy body weight. If you’re overweight, your risk of type 2 diabetes increases. (47)
Human studies suggest melatonin supports the release of signaling proteins that may help you manage your weight. More specifically, these signaling proteins may help control appetite, support calorie-burning, and promote insulin sensitivity. (48)
Animal research suggests melatonin may also improve mitochondrial function. In turn, this supports calorie-burning. (49)
Studies suggest melatonin has a protective role in your heart tissue and promotes cardiovascular health.
More specifically, melatonin may help: (50, 51, 52)
- Prevent cardiovascular damage from oxidative stress
- Inhibit fibrosis (scarring) of your heart tissue
- Support mitochondrial functioning in your heart cells
- Prevent your heart from enlarging (heart failure)
- Reduce blood pressure
Additionally, a human study suggests that higher levels of melatonin may improve your heart’s recovery after a heart attack. (53)
Lastly, melatonin’s ability to promote sleep could indirectly work to fend off chronic disease. Getting enough sleep is linked with reduced risk of heart disease, obesity, and type 2 diabetes. (54)
Support Your Melatonin Levels Naturally
A healthy diet and lifestyle can support your melatonin levels naturally.
Remember, you don’t just need melatonin at night to help you sleep. Your body uses melatonin in various organs and tissues regardless of the time of day. (2)
Diet and melatonin
As mentioned earlier, your body makes melatonin. The process starts with the amino acid tryptophan.
You get tryptophan in a wide variety of foods, like poultry, eggs, legumes, nuts, and seeds. Pumpkin seeds are an especially good plant source of tryptophan. (55, 56)
So, eating protein foods that are rich in tryptophan supports your melatonin production.
Interestingly, many foods also contain melatonin. Both plant- and animal-based foods contain melatonin.
Among animal foods, eggs and fish are top melatonin sources. In the plant category, nuts and many medicinal herbs are particularly rich sources of melatonin. (57, 58, 59)
Pistachios are a real standout for their melatonin content. Just 1 ounce (1/4 cup) of the shelled nuts pack 6.5 milligrams of melatonin. That’s as much or more than common melatonin supplements. (60)
Moreover, studies show that consuming melatonin via food helps raise levels of the hormone in your blood. (61)
Lifestyle and melatonin
You already know that blue light exposure in the evening hours can suppress your melatonin production at night. But, avoiding the light may seem challenging.
A simple way to support your melatonin production at night is to wear glasses with amber-colored lenses. These glasses filter out blue light. The spectacles are sometimes called blue blockers. Just slip them on during the two or three hours before bed. (62)
Additionally, getting sun exposure during the day can reduce the impact of blue light at night. For example, spend 15–30 minutes outdoors when you get up in the morning or at lunchtime. (63)
Another lifestyle practice that may support melatonin secretion is meditation or prayer. Meditation is a core component of Ayurveda, the natural health system that began in ancient times in India. (64)
Studies suggest that as little as 30 minutes of meditation at night could significantly increase your melatonin levels. (65, 66, 67)
A Multitasking Marvel
The idea that melatonin just helps you sleep has been “put to rest.”
Besides supporting sleep, melatonin may also:
- Aid digestive health, including regular bowel movements
Inhibit Candida overgrowth and parasitic infections
- Protect vital detox organs, including your liver and kidneys
- Help rid your body of chemical pollutants, heavy metals, and other toxins
- Shield your brain from mental and physical stressors
- Regulate your immune system to decrease allergy and autoimmune disease risk
- Reduce your risk of obesity, type 2 diabetes, and heart disease
Your body makes melatonin, and healthy lifestyle habits support its production. Many foods also contain melatonin.
Additionally, melatonin and binders complement each other's actions. Together, this team provides antioxidant protection, anti-inflammatory benefits, and powerful detox support.
Which melatonin function surprised you the most?