Does melatonin cause weight gain or weight loss?

If you’ve had trouble sleeping, you’ve probably heard of melatonin supplements. But you may have also heard that melatonin can affect your weight (for good or bad). So, what’s the verdict? Does melatonin cause weight gain or weight loss? 

The short answer: Melatonin isn’t known to cause weight gain. Because it promotes improved sleep, it may indirectly support weight loss.

Keep reading to learn more about melatonin and weight, including whether melatonin weight loss is real and if you should take melatonin for weight loss. 

If you’re wondering, “does melatonin make you gain weight?” you’re not alone. Melatonin is a hormone your body naturally produces to regulate sleep. People tend to think melatonin  causes weight gain because:

• Melatonin can cause daytime sleepiness, which can lead to sluggishness. This might result in reduced physical activity. But that doesn’t mean melatonin is the cause of weight gain.

• People who take melatonin usually take it to address poor or disrupted sleep. Sleep disturbances have been linked to weight gain. However, people may attribute that weight gain to melatonin instead of the underlying sleep issues. 

Bottom line: there isn’t any evidence that melatonin causes weight gain. In fact, some studies have found that taking melatonin may be linked to weight loss, which could be because melatonin improves sleep and poor sleep has been linked to weight gain. 

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So, this brings us to the question, “does melatonin make you lose weight?” The short answer is: probably not in any meaningful way. 

Research has shown that melatonin supplementation can help lower body weight in animals, especially those on a high-fat or high-sugar diet. In humans, the evidence is limited. A meta-analysis has shown melatonin was associated with a modest reduction in body weight (about 1.7 pounds) when taken in doses up to 8 mg. These effects were modest and not consistent across studies.

If melatonin affects weight at all, it’s likely indirect — through sleep and circadian rhythm regulation — rather than through any direct fat-burning effect.

More research is needed. For now, remember that melatonin isn’t considered a weight loss supplement. Evidence-based strategies like nutrition, physical activity, and sleep hygiene are far more effective for managing weight. 

If melatonin influences weight at all, it’s likely indirect. Its effects on the body that may help with wait are mainly related to sleep and circadian rhythm regulation. Better sleep can make it easier to manage appetite, activity, and energy balance during the day.

Early research suggests melatonin may support weight loss in other ways, too, including: 

• Appetite regulation Animal studies suggest melatonin may influence appetite.

• Energy use: Animal studies suggest melatonin may influence how the body uses energy, but this hasn’t been shown to cause weight loss in humans. 

• Insulin sensitivity: Some small studies report improved insulin sensitivity. While the clinical impact on weight is unclear, insulin sensitivity is known to support metabolic health.

• Relieving inflammation: Melatonin has anti-inflammatory properties. Lowering inflammation may also support metabolic health. 

• Regulating your circadian rhythm: This helps normalize your sleep-wake and eating-fasting cycles, which can optimize your body’s use of energy (calories) and promote weight loss.  

In other words, melatonin has a lot of potential effects on the body. While direct weight loss isn’t one of them, it could be an indirect result of these other effects. 

No. While melatonin supplements may indirectly support weight loss, more research is needed to determine if melatonin is actually effective for that purpose. Melatonin is typically used for sleep problems, such as jet lag, certain sleep disorders, and anxiety before or after surgery. 

If you’re looking to start an effective weight loss plan or you feel that poor sleep is interfering with your weight loss goals, consult your healthcare provider. They can discuss your options, including supplements that may help. 

Although there isn’t a single magic pill for weight loss, certain supplements for men and women may help support modest weight loss. In some cases, your healthcare provider may also consider prescription weight loss medications, such as Wegovy (semaglutide) and Zepbound (tirzepatide).  

It’s important to note that melatonin is sold as a dietary supplement. Dietary supplements are not approved or regulated by the United States Food and Drug Administration (FDA) for safety or effectiveness before they are sold to the public. It’s best to talk to a healthcare provider before starting melatonin. They can help you decide whether it’s right for you, and if so, which melatonin product and what dosage is best. 

Side effects and risks of melatonin 

While some drugs or supplements, like progesterone or nortriptyline, can cause weight changes as side effects, that’s not typically the case with melatonin. Short-term use of melatonin supplements is generally safe for most people. Common side effects include:

• Headache

• Dizziness

• Nausea

• Sleepiness

There isn’t enough information available to know if it’s safe to use melatonin long term. Other factors to consider before starting melatonin are:

• Drug interactions: Melatonin could interact with other drugs, such as epilepsy medications, blood thinners, and drugs that cause drowsiness. 

• Risk of allergic reactions: While uncommon, there may be a risk of allergic reactions when taking melatonin supplements. 

• Age: Melatonin may stay in the system of older people longer than in younger people. This can enhance the drug’s effects, possibly causing daytime drowsiness. 

• People with dementia: The American Academy of Sleep Medicine recommends against the use of melatonin in people with dementia because it could potentially increase the risk of falls. 

• People who are pregnant or breastfeeding: There isn’t enough information to know if melatonin is safe to use in people who are pregnant or breastfeeding, so it’s not recommended in these cases. 

Yes, there are several ways to boost melatonin naturally. While these strategies may indirectly support your weight loss goals, alone, they won’t lead to meaningful weight loss.

Here are some ways you can boost your body’s natural melatonin:

• Eat melatonin-rich foods: These include eggs, fish, nuts, and certain kinds of mushrooms. 

• Get morning sunlight: Getting out in the sunlight first thing in the morning helps regulate your circadian rhythm, which in turn, helps increase nighttime melatonin. 

• Exercise regularly: Regular physical activity can help boost melatonin production at night, improving the quality of your sleep. 

• Sleep in a dark room: Sleeping in as dark a room as possible encourages more melatonin production. 

• Limit screens at night: Screen time in the evenings can decrease melatonin and delay bedtime, reducing total sleep time. 

If you’re looking for an effective way to lose weight, melatonin isn’t the answer. Fortunately, there are many evidence-based methods you can try instead. These include healthy lifestyle habits and, sometimes, medical interventions.

Here are some alternatives you can consider: 

• Eating a balanced diet: Consuming a diet full of whole foods, such as fruits, vegetables, poultry, and fish, can help you feel fuller throughout the day, which can help you maintain a calorie deficit. 

• Consciously timing your meals: Intermittent fasting has been shown to be an effective weight loss strategy in some people. 

• Incorporating more physical activity: Engaging in regular exercise helps support successful, long-term weight loss, particularly in combination with a calorie deficit. 

• Prescription weight loss medications: If appropriate for you, some  prescription medications are safe and effective options for supporting weight loss. Popular options include Wegovy (semaglutide) and Zepbound (tirzepatide). Talk to your healthcare provider about whether you are eligible for prescription treatment.

• Getting adequate sleep: Lack of sleep increases hormones that control your appetite and calorie intake. That’s why sleeping well is important for weight loss. Aim for 7-9 hours of sleep per night to support a healthy metabolism. 

• Staying hydrated: There is evidence that water consumption increases the odds of achieving meaningful weight loss. The National Academy of Medicine recommends 3.7 liters of water per day for men and 2.7 for women.

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If you are taking melatonin, you may have wondered, “does melatonin cause weight gain?” Fortunately, melatonin isn’t known to cause weight gain. But it isn’t a proven or effective weight loss aid, either. Here are some key points to keep in mind if you’re searching for a “natural” way to lose weight: 

• Weight gain isn’t a known side effect of melatonin. However, poor sleep may lead to an increase in weight and melatonin might help you sleep better. 

• Melatonin is not an effective weight loss aid. 

• Naturally supporting melatonin in your body may support your weight loss goals. You can do this through eating melatonin-rich foods, exercising regularly, exposing yourself to sunlight in the morning, and limiting screens in the evening.

• Alternatives to melatonin for weight loss include eating a balanced diet, increasing physical activity, staying hydrated, and, in some cases, prescription weight loss medications.