Inadequate sleep can affect optimal body function and overall fitness. If you have trouble sleeping, you may have heard that melatonin might help. Melatonin is a naturally occurring hormone in the body. It can also be taken as a supplement.
According to research, not only can melatonin improve sleep patterns, but it also has other potentially beneficial effects on the body. It appears that melatonin can increase metabolism and weight loss and protect muscle tissue.
To better understand how a common sleep aid can help you lose body fat and build muscle, you should first learn how melatonin works in the body.
The role of melatonin
Melatonin (sometimes referred to as the “darkness hormone”) is secreted by the pineal gland in the brain to regulate our circadian rhythm. Our circadian rhythm works best when we have regular sleep patterns. It is also very sensitive to external signals such as sunrise and sunset.
When it gets dark outside and just before bed, our brain stimulates the release of melatonin, which makes us sleepy. Melatonin peaks in the middle of the night while we sleep. As the sun rises, melatonin levels drop, signaling the body to wake up.
Melatonin is the main hormone that regulates our circadian rhythm, which is why it’s important to address hormone imbalances if you’re having trouble sleeping.
Does Melatonin Help Reduce Body Fat?
Melatonin could boost metabolism and improve our ability to lose weight. To prove this theory, researchers conducted a study examining how melatonin affects body composition, lipid levels, and glucose metabolism in postmenopausal women
Menopause is a time in life when people can have a harder time shedding body fat and building muscle. For the small, randomized study, 81 postmenopausal women were supplemented with melatonin (1 mg or 3 mg per night) or a placebo for one year.
The study’s results, published in 2016, seemed to suggest that melatonin supplementation might have benefits beyond sleep.
The body composition of the participants was measured with a DXA scan before and after the trial period. Blood was drawn to record baseline and final levels of how melatonin affects leptin and adiponectin levels, as well as insulin levels. Together, these hormones help regulate the body’s metabolic processes (including fat burning and glucose regulation).
The participants supplemented with melatonin showed a 7% reduction in fat mass compared to the placebo group. They were also able to increase lean mass by 2.9% compared to the placebo participants. In addition, adiponectin levels increased significantly (by 21%) in the melatonin group.
Melatonin and lean body mass
Melatonin has been shown to increase lean mass in postmenopausal women. Other research has shown that the hormone also protects athletes from muscle damage
A balanced and protective internal environment is essential for muscle building. Oxidative stress occurs because there is an imbalance or impairment in the normal body function in response to intense exercise. This condition can lead to muscle fatigue and damage along with decreased energy.
Melatonin could reduce oxidative stress caused by exercise and create a better environment for muscle protection and growth. This could be because melatonin contains antioxidant properties that could potentially reduce oxidative stress caused by exercise.
In 2017, researchers conducted a study to examine the effect of melatonin on chemical reactions and muscle damage in resistance-trained athletes. During the short, randomized study, 24 athletes received either melatonin (100 mg/day—an amount significantly higher than what the body produces naturally every day) or a placebo.
During the test phase, the participants had to increase their training intensity. High-intensity exercise can cause the body to release chemicals that are potentially harmful to our muscles and cells. The researchers ran blood tests to check the levels of these chemicals, as well as enzymes and antioxidants beneficial for muscle growth, in the participants.
The results of the study suggested that:
- Athletes taking melatonin showed an increase in total antioxidant capacity for muscle protection compared to the placebo group.
- Melatonin supplementation appeared to prevent the increase in chemical toxins produced during oxidative stress compared to the placebo group.
- The participants who took melatonin had lower levels of harmful chemicals, suggesting they suffered less exercise-induced muscle damage from oxidative stress compared to the placebo group.
- The melatonin group retained higher levels of protective enzymes that help maintain muscle tissue compared to the placebo group.
- Total cholesterol levels were lower in the melatonin group compared to the placebo.
Additional Benefits of Melatonin
Melatonin is considered a powerful antioxidant and has been shown to improve immune function. Research has shown that melatonin’s antioxidant properties can help protect our bodies from free radicals (reactive molecules that are potentially harmful to the body) and cell damage
Several studies have shown that melatonin may have potential benefits beyond sleep, including:
- Brain health
- Cancer prevention
- Cognitive function during the natural aging process
- Reduced inflammation
- Fewer migraine headaches
- Heart health (angina pectoris, high blood pressure, reduced risk of heart attack)
- Improved gastrointestinal health
- Improved immune system
- Relief of depression caused by sleep disorders
- Remove free radicals
- Management of sleep disorders
Should You Take Melatonin?
The evidence seems to indicate that melatonin may be beneficial in improving our health and fitness. However, that doesn’t mean that a melatonin supplement is right for you. Your body may already be producing enough melatonin to support optimal fitness.
According to the National Institutes of Health (NIH), melatonin may help some people with sleep problems related to insomnia, jet lag, or shift work. Although the physiological dose (0.1 to 0.5 mg) of melatonin has been shown to help insomnia of certain types and to treat jet lag, the efficacy and safety of higher doses remain questionable.
It’s unclear if there’s enough evidence to support melatonin as a treatment for other conditions. Although research has uncovered some early positive clinical results, more research is needed. And like other dietary supplements, melatonin is largely unregulated by the Food and Drug Administration (FDA).
There is currently no evidence-based, commonly agreed recommended dose for melatonin supplements. Most studies start with a conservative dose (less than 0.3mg per day) — which is close to what our bodies naturally produce. Providers can make a general recommendation to start with the lowest dose needed to achieve the desired result.
There are also possible side effects of taking melatonin, including:
- Disruption of the circadian rhythm when too much is taken
- Drowsiness if taken during the day
- Drowsiness on waking after taking too much the night before
- Vivid dreams or nightmares
Some people report additional side effects such as stomach cramps, dizziness, headaches, irritability, decreased libido, and decreased sperm count in men.
Precautions to take before taking melatonin
Talk to your doctor about melatonin supplementation and keep the following precautions in mind:
- Depression: Some studies have shown that melatonin can worsen symptoms of depression in some people.
- Drug Interactions: Melatonin may interact with certain prescribed medications.
- Pregnancy: People who are pregnant or breastfeeding should not take melatonin.
- Side Effects: Taking high doses of melatonin has been associated with daytime sleepiness, hyperprolactinemia, hypothermia, and reduced exercise capacity.