Sleep can be hit or miss on some days. During stressful times in your life, you might find it tough to get the recommended seven to nine hours of rest for several nights in a row. Missing out on sleep can really hurt your productivity the next day, which only adds more stress as you try to push through with a sluggish brain. When poor sleep becomes a long-term pattern, it can increase the risk of serious health problems such as high blood pressure.
One way to support better sleep is by turning to melatonin, often called the sleep hormone. Your body naturally produces melatonin in the pineal gland, which responds to signals from your eyes when daylight starts to fade. This rise in melatonin is what helps you feel sleepy at night. While you can take a melatonin supplement to make it easier to fall asleep, research suggests it may do more than just improve your rest.
Melatonin could also help lower blood pressure. Even though blood pressure naturally drops a little at night, studies have found that melatonin may be beneficial for people with high blood pressure as well as for healthy people who consume a lot of sodium.
How melatonin may help people with high blood pressure
Some people who have high blood pressure still can’t keep it under control, and uncontrolled high blood pressure can lead to heart disease and stroke. Even if some people may respond well to blood pressure medication, they still may have trouble keeping their blood pressure down at night, when it usually dips. People who have high blood pressure at night tend to have a higher risk of cardiovascular issues.
Researchers believe that melatonin may help open up blood vessels and reduce stress signals that often cause high blood pressure. A 2022 meta-analysis in the Journal of Clinical Hypertension pulled the results of four clinical trials that looked at the effect of melatonin supplementation on people with high blood pressure. When people took controlled-release melatonin, their nighttime systolic blood pressure (the top number) was lowered by an average of 3.6 millimeters of mercury (mmHg) after three or four weeks. However, taking a 5-milligram dose of immediate-release melatonin at night didn’t affect nighttime blood pressure.
You may think about melatonin as a sleep supplement, but it can also be taken during the day to reduce blood pressure. A 2020 study in the European Cardiology Review had 30 men with high blood pressure take a 3-milligram dose of melatonin in the morning while wearing a continuous blood pressure monitor. Compared to the previous day, their daytime systolic blood pressure dropped by 5 points and diastolic by 3 points. Their nighttime blood pressure did not change.
How melatonin affects people with normal blood pressure
The American diet is often loaded with sodium thanks to fast food and ultra-processed convenience foods. Sodium causes you to retain more water, which increases the volume of blood running through your blood vessels. This requires the heart to work harder to pump oxygen and other nutrients through your body. Sodium also causes your arteries to narrow, adding more pressure for your heart and arteries.
A 2023 study in the American Journal of Physiology investigated how melatonin may counterbalance the effect of sodium in young, healthy adults who don’t have high blood pressure. All the people in the study were told to eat a diet of about 2,300 milligrams of sodium, which is within the recommended sodium limit per day. They also took salt pills, which added another 4,600 milligrams to their dietary intake. That’s almost three times the recommended upper limit for sodium each day.
(Is it safe to take melatonin every night?)
For 10 days, one group took 10 milligrams of melatonin while the other group took a placebo, and their 24-hour blood pressure was measured using a continuous blood pressure monitor. After two weeks, the groups switched. When the people took the melatonin, their nighttime systolic blood pressure dipped by an average of 4 to 5 mmHg. However, their 24-hour blood pressure didn’t differ from taking the melatonin versus the placebo.