A cardiologist says she's seeing a rise in 20-somethings with heart arrhythmias caused by herbal supplements

• Cardiologists told Insider people under 30 are developing heart problems from taking herbal supplements.
• Common supplements like fish oil and bitter orange have been linked to heart problems.
• Loose federal regulations mean supplements may contain unlisted, risky ingredients.

Cardiologists are sounding the alarm on herbal supplements, which are giving their young patients heart problems.

California-based cardiologist Dr. Danielle Belardo said the most common cause of heart arrhythmia, or irregular heartbeat, presenting in her 20-something patients stems from taking herbal supplements.

Belardo said her patients come in taking herbs like bitter orange and ephedra, both linked to irregular heartbeats in case studies and clinical research.

It's not always straightforward to sort out which compound is the culprit, since Belardo's patients often take multiple supplements, and the supplement trend is growing faster than researchers can keep up.

"This is drawing on the cusp of what we know with regards to herbal supplements and arrhythmia," Belardo told Insider. "Since there's such poor regulation of the formulation, the purity, and the efficacy of these herbals, we don't have any robust literature to tell us exactly what's causing what."

Belardo isn't the only doctor raising the alarm

The US does not closely regulate the $1.5 trillion wellness industry, meaning supplement makers are not required by law to provide proof of safety or strength of their product.

However, the number of Americans taking dietary supplements has exploded since the COVID-19 pandemic's start. In Southern California, Belardo says she often sees patients with heart problems who "gravitate towards alternate therapies and herbals and supplements."

Now, Belardo says, she has started probing her patients on what over-the-counter pills they take — and she isn't alone.

After tweeting out to her 70,000 followers that she was seeing young people sickened by supplements, she had other cardiologists, ER doctors, and internists around the country say they've experienced the same phenomenon.

Dr. Martha Gulati, a California-based cardiologist and president-elect of the American Society for Preventive Cardiology, is among them. Gulati told Insider she is concerned that many people falsely believe taking "natural" remedies means the items are safer than pills made in a lab.

"I think that's reflective of the growing alternative medicine, and, essentially, pseudoscience in this space," Belardo said.

Emerging evidence that popular supplements are linked to heart problems

As Belardo mentioned, trying to find evidence to support the benefits or risks of a supplement is tricky. There are few robust studies to go by, so most of the evidence we have comes in the form of case studies — individual cases that doctors report in journals or articles.

Insider has reported on cases where patients showed up to the hospital with serious health problems from taking vitamin, herbal, and hormone supplements.

Supplements that have been linked to arrhythmia in published research include:

• Bitter orange, also called citris aurantium, has been linked to arrhythmia, per Belardo. The National Institutes of Health acknowledges bitter orange might cause irregular heartbeat, but said more research is needed to show a direct link.
• Ephedra and ephedrine alkaloids, compounds the US banned in 2004 for causing arrhythmia, heart attack, stroke, and death. The compound still shows up in supplements despite the ban: a 2021 case study of a 56-year-old with an arrhythmia showed he took an herbal pill containing ephedrine alkaloids.
• Fish oil, taken at a dose of one gram a day or more, might increase the risk for a type of irregular heart rhythm called atrial fibrillation, according to several clinical studies. Gulati said fish oil can also interact with blood thinners to cause dangerous bleeding.

There are question marks on other supplements, such as ashwagandha, an evergreen shrub touted by celebrities for its perceived stress-reduction. The herb might have caused arrhythmia in some case studies, Belardo said, including one 2022 report that suggested the herb caused arrhythmias in a 73-year-old woman. The heart condition stopped when she no longer took ashwagandha. Researchers have not found a link between ashwagandha and heart problems in clinical studies.

Stop believing everything you hear on social media, cardiologists say

Belardo acknowledges the appeal of alternative medicine, particularly for patients who might feel neglected by the medical system. But she has seen first-hand that people are getting health advice from social media, and often it isn't true. And while young people are typically at a lower risk for arrhythmia, that doesn't mean they're immune.

"The truth is, when you look at sometimes the top health podcasts or the top health influencers, oftentimes they are not people who are recommending guideline-based, evidence based-medicine recommended by all the major academic medical organizations," Belardo said. For evidence-based advice, she recommended checking guidance from the American College of Cardiology and the American Heart Association.

Gulati agreed, warning that the current fanfare over natural supplements can be alluring and misleading.

"Be an informed consumer, don't be influenced by social media," Gulati said. "Be smart about what you're putting into your body and do a little bit of research about it. Just because it's sold over-the-counter doesn't make it safe."

Have you experienced health problems, or had a patient experience health problems, due to supplements? Email the author at aakhtar@insider.com.