Six supplements people commonly take for heart health didn’t help lower “bad” cholesterol or improve heart health, according to a study published Sunday, but statins did.
Some people believe that common dietary supplements – fish oil, garlic, cinnamon, turmeric, plant sterols and red yeast rice – will lower their “bad” cholesterol. “Bad” cholesterol, known in the medical community as low-density lipoprotein, or LDL, can cause fatty deposits to build up in the arteries. Fatty deposits can block the flow of oxygen and blood that the heart needs to function, and the blockage can lead to a heart attack or stroke.
For this study, which was presented at the 2022 American Heart Association Scientific Sessions and published concurrently in the Journal of the American College of Cardiology, researchers compared the impact of these particular supplements to the impact of a low dose of a statin—a cholesterol- reduction in medication – or a placebo, which does nothing.
The researchers made this comparison in a randomized, single-blind clinical trial involving 190 adults with no prior history of cardiovascular disease. Study participants were aged 40 to 75, and different groups received a low-dose statin called rosuvastatin, a placebo, fish oil, cinnamon, garlic, turmeric, plant sterols, or red yeast rice for 28 days.
The statin had the greatest effect and significantly reduced LDL compared to supplements and placebo.
The mean reduction in LDL after 28 days on a statin was nearly 40%. The statin also had the added benefit of total cholesterol, which was reduced by an average of 24%, and blood triglycerides, which were reduced by 19%.
None of the people who took the supplements saw a significant reduction in LDL cholesterol, total cholesterol, or blood triglycerides, and their results were similar to those of people who took a placebo. While there were similar side effects in all groups, there was a numerically higher number of problems among those who received plant sterols or red yeast rice.
“We designed this study because many of us have had the same experience of trying to recommend evidence-based treatments that reduce cardiovascular risks to patients and then having them say ‘no thanks, I’ll just try this supplement,'” said study partner. -author Dr. Karol Watson, professor of medicine/cardiology and co-director, UCLA Program in Preventive Cardiology. “We wanted to design a very rigid, randomized, controlled trial study to prove what we already knew and show it in a rigorous way.”
Dr. Steven Nissen, a cardiologist and researcher at the Cleveland Clinic and co-author of the study, said patients are often unaware that dietary supplements are not tested in clinical trials. He calls these supplements the “snake oil of the 21st century.”
In the United States, the Dietary Supplement and Health Education Act of 1994 severely limited the US Food and Drug Administration’s ability to regulate supplements. Unlike pharmaceutical products that must be proven safe and effective for their intended use in order for a company to market them, the FDA does not need to approve dietary supplements to be sold. Only after they are on the market and proven to be unsafe can the FDA step in to regulate them.
“Patients think studies have been done and they’re just as effective as statins and they can save them because they’re natural, but natural doesn’t mean safe and doesn’t mean they’re effective,” Nissen said.
The study was funded through an unrestricted grant from AstraZeneca, which manufactures rosuvastatin. The company had no data on methodology, data analysis and discussion of clinical implications, according to the study.
The researchers acknowledged some limitations, including the study’s small sample size, and that the 28-year study period may not capture the effect of the supplements when used for longer.
In a statement Sunday, the Council for Responsible Nutrition, a trade association for the dietary supplement industry, said “supplements are not intended to replace drugs or other medical treatments.”
“Dietary supplements are not meant to be quick fixes, and their effects may not be revealed during a study lasting only four weeks,” Andrea Wong, the group’s senior vice president of scientific and regulatory affairs, said in a statement.
Dr. James Cireddu, an interventional cardiologist and medical director of the University Hospitals Harrington Heart & Vascular Institute at University Hospitals Bedford Medical Center, said the work will be helpful.
“They did a good job collecting data and looking at the results,” said Cireddu, who did not work on the study. “It will probably resonate with patients. I get asked all the time about supplements. I think that does a good job of providing evidence.”
Dr. Amit Khera, chair of the AHA Scientific Sessions programming committee, did not work on the research, but said he thought this was an important study to include in presentations this year.
“I take care of patients every day with these exact questions. Patients always ask about supplements instead of or in addition to statins,” said Khera, who is professor and director of preventive cardiology at UT Southwestern Medical Center. “I think if you have high-quality evidence and a well-designed study, it’s very important to help educate patients about the value, or in this case the lack of value, of some of these supplements in reducing cholesterol”.
Statins have been around for more than 30 years and have been studied in more than 170,000 people, he said. Consistently, studies show that statins reduce the risk.
“The good news is, we know statins work,” Khera said. “That doesn’t mean they’re perfect. That doesn’t mean everyone needs one, but for those at higher risk, we know they work and it’s well proven. If you’re going to do something different, you have to make sure it works.”
With supplements, she said she often sees misinformation online.
“I think people are always looking for something ‘natural’ but you know there are a lot of problems with that terminology and most importantly we have to ask do they work? That’s what this study does,” adds Khera. “It’s important to ask, are you taking something that’s proven, and if you do this and you don’t, that’s instead of proven treatment. It’s a real concern.”
