Omega-3 Supplements Are No Substitutes for Prescribed Products

It’s never a good idea to substitute over-the-counter dietary supplements in place of a doctor’s advice or instead of properly prescribed medications. And this definitely applies to popular “fish oils containing omega-3” fatty acid products, which include supplements promoted extensively as helping lower cholesterol levels that put people at greater risk for heart disease.

Most dietary omega-3 supplements, and most prescription omega-3 formulations, contain EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Products containing both EPA and DHA can have different impacts on low-density lipoprotein cholesterol (LDL-C) — most commonly known as the “bad cholesterol.”

EPA and DHA are the primary omega-3 fatty acids believed to have cardiovascular benefits.  Dietary supplements have varying levels of DHA and EPA, and often, high levels of other fats including saturated fats. Prescription omega-3 medications are pure omega-3. Some have combinations of EPA and DHA, and one is even a pure EPA which may have additional lipid benefits compared to the EPA-DHA combination.

EPA and DHA levels are believed to be beneficial for effectively modifying lipid levels (amounts of fatty acids and cholesterol in the blood) in people with heart disease risk factors, says Jonathan Fialkow, M.D., medical director of chest pain center, cardiac rehabilitation and stress lab at Miami Cardiac & Vascular Institute at Baptist Hospital. Dr. Fialkow is also a certified lipidologist. Omega-3 medications are also prescribed to lower the risk of pancreatitis, a life-threatening condition which can occur with very high triglyceride levels.

In a new article published in the American Journal of Cardiovascular Drugs authored by Dr. Fialkow, he cautions against the use of dietary supplements as a substitute for prescribed medication. Omega-3 dietary supplements containing fish oils are heavily promoted for heart health or for their anti-inflammatory qualities that can help people manage arthritis and joint pain. But there is no clinical data supporting these claims.

‘Not Approved or Intended to Treat Disease’

“Omega-3 fatty acids are essential parts of our diet. However, fish oils in omega-3 dietary supplements contain lower levels of EPA and DHA than prescription products and are not approved or intended to treat disease,” says Fialkow. He adds that cold-water fish and seafood tend to have high levels of omega-3 fats.

Prescription omega-3s are meant to treat lipid abnormalities, such as elevated triglycerides, which may have an impact on heart disease. Over the last decade, several prescription omega-3 fatty acid products have been approved by the U.S. Food and Drug Administration based on data from clinical intervention trials. But fish oil containing omega-3 supplements are not regulated by the FDA.

“There are issues and concerns regarding the content, quality, and purity of omega-3 fatty acid dietary supplements,” says Dr. Fialkow. “It is important to recognize that dietary supplements do not always contain what is specified on their label and may differ in EPA and DHA content from batch to batch.”

Prescription Omega-3s Proven Effective

Prescription omega-3 fatty acid products have proven to be safe and effective in reducing elevated levels of triglycerides and harmful LDL-containing particles, such as triglyceride rich lipoproteins..  Triglycerides, the end product of digesting and breaking down fats and carbohydrates in foods, are measured using a common test called a lipid panel. It’s the same blood test that checks “good” and “bad” cholesterol levels.

The cardiovascular benefit of reducing triglycerides has not been conclusively proven, Fialkow says. “But emerging evidence from recent studies suggests that triglycerides and triglyceride-rich lipoproteins play a causal role in coronary atherosclerosis,” he says.  Atherosclerosis refers to the build- up of a waxy plaque on the inside of blood vessels. It’s a major component of heart disease and the ultimate cause of heart attacks and strokes and death.

“Subsequent diet-based studies suggested that increased omega-3 fatty acid consumption reduced cardiovascular mortality in high-risk (but not low-risk) individuals,” Fialkow writes in his article.

The National Institutes of Health says that there is some evidence that omega-3s found in seafood and fish oil may be modestly helpful in relieving symptoms of rheumatoid arthritis. However, “for most other conditions for which omega-3s have been studied, definitive conclusions cannot yet be reached, or studies have not shown omega-3s to be beneficial,” NIH says.

Supplements Vary Widely in Doses and Ingredients

A prescription product goes through rigorous testing to determine safety and a proven medical benefit. Dietary supplements are not regulated, cannot make a health claim and, in the case of fish oils, often do not have the amount of omega-3 on the label, Fialkow says. Supplements also have a high level of non-healthy fats, such as saturated fats, and often may be oxidized in its manufacturing which can make them harmful.

Dr. Fialkow’s article stresses the importance of consulting with a physician and, if omega-3 medication is prescribed, not substituting with fish oil dietary supplement. Studies are currently being conducted to determine whether omega-3 prescription products actually decrease cardiovascular events and death. Preliminary reports are expected before the end of the year.