The fish oil supplements taken by millions around the world to reduce the effects heart disease may not be as beneficial as once believed.
People have been taking capsules of omega-3 supplements for decades to improve heart health. However, in a recently published study by the London-based Cochrane Heart Group, scientists believe there actually may be little to no benefit taking these additives.
The study was led by Dr. Lee Hooper from the University of East Anglia in England. His team conducted a meta-analysis involving 79 studies and over 112,000 people.
By looking at diverse populations of men and women from North America, Europe, Australia, and Asia, the researchers found “little or no difference to risk of cardiovascular events, coronary heart deaths, coronary heart disease events, stroke, or heart irregularities,” among those taking the supplement, according to a released statement by Cohrane.
The researchers found that these omega-3 fatty acids also had little to no meaningful effect on the risk for death from any cause. In those who increased their intake of omega-3 fats, the risk for death from any cause is 8.8 percent. Those who didn’t increase their intake of omega-3 fats had a 9 percent risk for death from any cause. This 0.2 percent difference is considered statistically insignificant.
“Results of a large meta-analysis showed that omega-3 polyunsaturated fatty acid supplements don’t provide any protection against cardiovascular disease events” said Dr. Marcin Kowalski, director of Cardiac Electrophysiology at Staten Island University Hospital in Staten Island, New York.
“Results of the study aren’t surprising given a borderline benefit shown in previous small studies with multiple biases,” he explained.
Although these findings may not be new as there’s been controversy regarding omega-3 fatty acids for many years, this is the first study to compile this magnitude of data.
What are omega-3 fatty acids?
Omega-3 fatty acids are a type of fat naturally found in the environment. There are three fatty acids that make up omega-3s, two of which the body can make on its own. Alpha-linolenic acid (ALA) is found in vegetable oils, nuts, and seeds and can’t be made by the body. However, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which the body makes from ALA, can be found in oily fish and fish oils such as cod liver oil.
Historically, fish oils were used at the start of the 20th century in Northern Europe, and other areas that were sunlight-poor, to prevent rickets, or severe vitamin D deficiency. Fish oil, particularly cod liver oil, has large amounts of vitamin A, vitamin D, and omega-3 fatty acids.
Through association studies — studies that don’t show a direct correlation — researchers found that those who lived in Greenland consumed a diet that was high in omega-3 fatty acids.
These individuals also had lower rates of coronary heart disease. In turn, a correlation was assumed that omega-3 fatty acids were the reason for this heart disease benefit when no direct correlation studies were conducted.
After these studies were published, omega-3 became popular as a supplement.
According to San Francisco-based Grand View Research, the global omega-3 supplement market size was valued at over $33 billion in 2016. This is a significant portion of the global dietary supplement market size of $133 billion.
In a 2007 study conducted by the National Health Interview Survey, 17.7 percent of American adults had used supplement products in the United States with the largest percentage of individuals using fish oil, omega-3, or DHA products.
Finding a way to combat heart disease is a priority for the medical community and many hoped that these supplements would help. According to the Centers for Disease Control and Prevention, 610,000 people die from heart disease in the United States every year. That includes 1 in every 4 deaths. Coronary heart disease is the most common type of heart disease accounting for over 370,000 deaths.
“We can be confident in the findings of this review which go against the popular belief that long-chain omega-3 supplements protect the heart,” said Hooper in a press release. “This large systematic review included information for many thousands of people over long periods. Despite all this information, we don’t see protective effects,” he explained.
Kowalski believes this study will help both patients and physicians make better decisions.
“This study will provide more information and resources for physicians and patients to make a more informed decision as to the benefits of the medication,” Kowalski said. “Physicians now can refer not only to the recommendations from leading professional organizations for guidance but also to this study.”
With this study showing omega-3 supplements providing minimal cardiac health benefits, the American Heart Association continues to recommend a balanced diet.
A variety of fruits and vegetables can be added to a diet rich in skinless poultry and non-fried fish. Fish, such as salmon or trout, provides a low-calorie option with high protein content.
Health experts continue to promote regular exercise, limited alcohol consumption, and not smoking as simple lifestyle changes to create meaningful benefit to one’s heart health.