Dietary Supplements Don’t Lower ‘Bad’ Cholesterol, Study Finds
Supplements like fish oil, turmeric, and cinnamon that are often touted for their heart benefits have no impact on ‘bad’ cholesterol, a major risk factor for heart attacks and strokes, a new study reports.
Dietary supplements often marketed as good for the heart may not be worth taking, according to new research presented at the American Heart Association’s (AHA) Scientific Sessions 2022.
Results from the study, also published in the Journal of the American College of Cardiology (JACC), found that six dietary supplements widely used for heart health didn’t help lower low-density lipoprotein (LDL) cholesterol, or the “bad” cholesterol, which can contribute to plaque build up in blood vessels and lead to blood clots and heart attacks.
For the study, scientists wanted to see if any of the supplements — fish oil, garlic, cinnamon, turmeric, plant sterols, and red yeast rice — could reduce the “bad” kind of cholesterol. To find out, they randomly assigned 190 adults without any history of heart disease to take one of the six supplements, a placebo, or a low-dose statin — a cholesterol-lowering drug — daily for four weeks.
By the end of the study, none of the supplements reduced LDL cholesterol levels significantly more than placebo. But the statin pill, a 5-milligram dose of rosuvastatin (Crestor), reduced LDL cholesterol about 35 percent more than placebo.
“Americans spend an estimated $50 billion on dietary supplements annually, and many are marketed for ‘heart protection’ or ‘cholesterol management,’ yet there is minimal to no research demonstrating these benefits,” says lead study author Luke Laffin, MD, co-director of the Center for Blood Pressure Disorders at the Cleveland Clinic in Ohio.
“Some people also believe supplements are as effective or more effective than cholesterol-lowering statin medications,” Dr. Laffin says.
Roughly half of Laffin’s patients took one of the six supplements tested in the study — this was one reason researchers decided to test how well they worked, he adds. One concern was that patients were refusing proven treatments and trying supplements instead. “Worse still is patients stop taking medications like statins and take supplements in their place,” Laffin adds.
In the study, half of the patients in the statin group had their LDL cholesterol drop by more than 40 percent.
Side effects were similar across all the groups in the study. However, an estimated 23,000 emergency room visits in the United States each year are due to adverse events related to dietary supplements, the study team wrote in JACC.
Beyond its small size, another limitation of the study is that it only lasted four weeks. It’s possible that the safety or effectiveness of the supplements or statin drug might look different in a longer, larger trial.
The U.S. Preventive Services Task Force, an influential independent medical advisory panel, in August recommended that people ages 40 to 75 at high risk for heart disease take statin therapy to prevent a first heart attack or stroke. Factors that can put people at high risk include high cholesterol, high blood pressure, diabetes, and smoking.
Many patients taking statins use doses much higher than what researchers tested in the new study. Guidelines from the AHA and ACC, for example, recommend that some people with the highest risk for heart disease go on high-intensity statin therapy that aims to cut LDL cholesterol levels in half. Under these guidelines, the highest risk patients might take 20- to 40-milligram rosuvastatin pills each day.
Statins aren’t the only intervention these guidelines emphasize. AHA also recommends that people get all the nutrients they need by eating a variety of foods instead of using supplements. And, AHA encourages people to get plenty of exercise and follow a heart-healthy diet such as a Mediterranean-style diet that’s heavy on vegetables, fruits, legumes, nuts, olive oil, whole grains, and fish, and limits red and processed meat.
Supplements may just add an unnecessary layer to the many things people can do to promote heart health that have a proven track record, says Manesh Patel, MD, chair of the AHA’s Council on Scientific Sessions Programming and chief of cardiology at Duke University School of Medicine in Durham, North Carolina.
“The main harm is that they would cause confusion and less use of things that work to improve heart health,” Dr. Patel says. “They also increase the costs and complexity for people to ensure good heart health through both behaviors and medical therapy.”