Separating fact from rumor
It’s important to clear up one thing right off the bat:
There are currently no proven links between melatonin supplements and heart
disease or problems. So, you can rest a little easier if you’ve been worried.
But that doesn’t mean melatonin is risk-free — or even the
right solution for your needs.
Cardiologist Michael Hill, MD, walks us through the research.
Does melatonin use cause heart failure?
There’s no clear evidence that melatonin causes heart failure.
So, why the chatter? It’s because researchers found possible links between
melatonin and heart failure. They used a health records database to compare two
groups of adults with insomnia — those who took melatonin for at least one
year, and those who didn’t.
They found that within a five-year period, the melatonin
group had higher rates of:
- Heart
failure
- Hospitalization
for heart failure
- Death
from any cause
“These are striking findings, and that’s why they made
headlines,” Dr. Hill acknowledges. “But there are some important caveats.”
Dr. Hill explains:
- There’s
no proof that melatonin caused heart failure: The
research makes associations, but it doesn’t prove causation. That’s a huge
distinction. It means there are patterns, but there’s no proof that
melatonin is the driving factor.
- The
findings aren’t peer-reviewed: “This is a research abstract, meaning a
presentation of preliminary data,” Dr. Hill notes. “It must go through
rigorous peer review before we accept the findings as fact.”
- Gaps
remain: Because these are early findings, we don’t know the factors,
like melatonin supplement dosage or treatments given to the non-melatonin
group. We also don’t know if some people had sleep apnea or other
diagnoses.
- Heart
failure can cause sleep issues: It’s possible that some study
participants had issues because they were already in the
early stages of heart failure and didn’t yet have a diagnosis. That would
add more gray area to the findings.
“Based on the information available so far, we can’t say
that melatonin causes heart failure,” Dr. Hill clarifies. “But the topic is on
our radar, and we’ll continue learning.”
Can it cause other heart issues?
There’s not enough evidence to say that melatonin causes
other problems, like heart palpitations or an increased heart rate.
One study from 2017 found possible associations
between melatonin use and premature ventricular contractions
(a common and typically harmless arrhythmia). But that study only looked at two
adults. We’d need much more evidence to prove any links.
Why you might be feeling palpitations
So, if you’re taking melatonin and notice your heart racing,
skipping a beat or flip-flopping, what’s up? Dr. Hill offers insight.
“Palpitations or an increased heart rate may be due not to
the melatonin, but rather to sleep apnea,” he says. “This common disorder is
associated with both slow or fast abnormal heart rhythms and irregular beats,
which can cause those unusual sensations.”
Many people don’t even realize they have sleep apnea. But
red flags include waking up tired every morning and needing naps to get through
the day. If this sounds familiar, talk to a healthcare provider — especially if
you’re noticing palpitations.
Possible benefits of melatonin for your heart
Now that we know there aren’t proven risks, you may be
wondering: Can melatonin do your heart any good? Maybe, according to some
evidence.
“Some randomized clinical trials have shown possible
benefits of melatonin,” Dr. Hill shares. He notes that in a randomized
trial of people with heart failure, those taking melatonin for six months
saw improvements in:
- Symptoms
- Quality
of life
- A
blood marker called NT-proBNP (which usually reflects heart failure
symptom burden)
“While this is a small study, it offers high-quality
evidence that warrants further research,” he adds.
That’s right — some findings seem to contradict the research
abstract! This might feel confusing. But that can be the nature of medical
research. There’s not a single path going in one direction. Researchers
explore all avenues to learn as much as they can, even if that
means grappling with conflicting data.
“Another study has found possible links between melatonin
and reduced blood pressure and cholesterol levels,” Dr. Hill says.
“Melatonin likely isn’t the direct cause. But it could be helping you sleep
better. And that, in turn, helps manage your blood pressure, cholesterol and
other heart disease risk factors.”
Better sleep lowers cardiovascular disease risk
It’s a well-established fact that better sleep translates to
a lower risk of heart and blood vessel problems. The opposite is also true —
poor sleep raises your risk of cardiovascular disease.
Sleep is so important that the American Heart Association
lists “get healthy sleep” as one of “Life’s
Essential 8” measures for improving cardiovascular health. These are eight
steps we all should try to take to protect our hearts.
But good sleep can be hard to come by. Enter melatonin. It
may help shift your body’s circadian clock so you sleep soundly and wake up
feeling rested.
If melatonin helps you sleep better, that’s great. But Dr.
Hill cautions that it’s not meant for long-term use.
Short-term use is best
“Melatonin is best used on a temporary basis,” Dr. Hill
emphasizes. “If you’ve needed it for months or years to achieve good quality
sleep, talk to your primary care provider or even a sleep specialist.”
Dr. Hill describes why limited use is best:
- Melatonin
may mask the reason for poor sleep. Taking melatonin as a sleep aid
may help you snooze, but it won’t reveal the root cause of sleep issues.
And that means you may go months or years without effective treatment for
sleep apnea, insomnia or other conditions.
- Long-term
melatonin use may not be safe. “Less is known about the risks of
long-term supplementation,” Dr. Hill states. “So, it’s a good idea to
limit use to temporary situations, like when you’re traveling or trying to
adjust your bedtime.”
- Melatonin
supplements aren’t regulated. In the U.S., melatonin is an
over-the-counter supplement, not a prescription drug. That means the U.S.
Food and Drug Administration (FDA) doesn’t regulate its dosage or quality.
Talk with your doctor about safety
If you decide to use melatonin, talk with a healthcare
provider first. They’ll make sure:
- It’s
safe for you based on your health history.
- It
won’t interact with any medications you’re taking.
- You’re
aware of possible side effects, like dizziness, headaches and daytime
drowsiness.
“Some research shows that melatonin may adversely
affect blood sugar variations in people with diabetes,” Dr. Hill
warns. “That’s just one example of a scenario where we’d want to be extra
careful in using melatonin, even just for a few days.”
Make quality sleep a priority
Whether or not you’re taking melatonin, one thing’s for
sure: Sleep is vital for your heart.
If a good night’s sleep feels like an impossible dream, it’s
time to talk to a healthcare provider about treatment options. They’ll go over
the possible causes, from excess stress, circadian disruptions and poor sleep
hygiene to diagnosable conditions like sleep apnea or insomnia.
“There’s no need to toss out your melatonin based on any of
this latest research,” he says. “But ideally, it’ll mostly stay in your
cabinet. Work with your provider to find sustainable, long-term solutions to
the sleep issues you’re facing.”
