What Pharmacists Need to Know About Omega-3 Fatty Acids and Fish Oil Supplements

Pharmacists appreciate the value of omega-3 fatty acids for patients with cardiovascular disease and fish oil supplements are a frequently suggested method for people to increase their intake of this important nutrient. However, findings from extensive research into omega-3s may be surprising.

For well over 10 years, my colleagues at Elucida Research and I have been investigating the biological properties of omega-3 fatty acids and how they protect the heart to prevent serious cardiovascular events, like heart attacks or strokes. Omega-3 fatty acids are considered essential fatty acids as our bodies do not produce them so we must obtain them from the food we eat and other sources.

Great sources of omega-3s include oily fish, such as salmon and mackerel, but unfortunately, not all fish are the same with respect to their omega-3 content. For example, tilapia has become popular both for home cooks and on restaurant menus, but tilapia contains 10 times less omega-3 than salmon. Instead, tilapia has more omega-6 fatty acids, which are considered proinflammatory and actually negate many of the benefits of omega-3s.

Fish Oil and Omega-3 Fatty Acids

Many patients turn to fish oil supplements to gain the benefits of omega-3 fatty acids, but there are important considerations pharmacists should be aware of before recommending fish oil supplements to their customers.

While many people do turn to fish oil dietary supplements to augment or replace fish in their diet, our laboratory has been studying the quality of these supplements to better understand if they are in fact a safe and effective alternative to fresh fish or even prescription omega-3 fatty acids. What we have learned and published over the years has raised serious quality concerns, in 3 important ways:

1. The amount of beneficial omega-3s in these supplements often make up only one-third or less of the total oil in the product and levels can differ from what is advertised and even from lot to lot.
2. When we investigated what other oils are in these products, we found that they included those that are not considered heart healthy, including saturated fats. As you know, saturated fats and their high caloric content are not recommended for patients with cardiovascular disease (CVD) or at high risk for CVD.
3. In addition to concerns with the variable amounts of omega-3 fatty acid and the presence of other “unhealthy” oils, we also found that the beneficial omega-3s themselves were often oxidized or rancid due to poor manufacturing processes. And consumption of rancid oils is certainly not advisable for patients with high risk or existing CVD since they promote inflammation.

Commonly Held Misconceptions

Through a decade of research, we have seen many misconceptions when it comes to understanding omega-3 fatty acids and fish oil supplements but there is one that arises more frequently than others. I hear people refer to fish oil supplements as OTC or over-the-counter omega-3 fatty acids.

This implies a level of regulation that does not exist. OTC medications are under FDA scrutiny whereas fish oil supplements do not have such careful regulation. Therefore, pharmacists are advised to clear up the confusion with customers.

It’s important that pharmacists make it clear that fish oil supplements are not an appropriate substitute to prescription products directed by their health care provider. There is currently no approved OTC fish oil or omega-3 product. Pharmacists should also know that the investigative research we’ve published has been replicated by a number of other independent academic laboratories.

It has been verified that widely used fish oil supplements have oxidized or rancid oils and that the amounts of actual omega-3 levels often deviated from what’s advertised.

Prescription Omega-3 Fatty Acid Options

Along with common store shelf fish oil supplements, we thought it was important for our lab to also look at the prescription omega-3 fatty acid product. We found that, due to the careful FDA regulation and manufacturing oversight, the prescription product did not have the same problems with respect to content or the presence of contaminants like oxidized oils.

With respect to prescription omega-3s, there are also significant content differences among these products. There are older products that have mixed omega-3s, whereas a newer formulation contains only purified eicosapentaenoic acid (EPA). Large clinical outcome trials have demonstrated that this formulation of omega-3 fatty acids is critically important with respect to proven cardiovascular benefits.

Additional Points Pharmacists Need to Consider About Omega-3s and Fish Oil Supplements

• Our laboratory has published extensively on the comparative biological actions of different omega-3 fatty acid formulations. In particular, we and others have demonstrated that EPA specifically targets and benefits the blood vessels in patients with heart disease and it does so better than older mixed omega-3 fatty acid formulations.
• The imperative of receiving effective treatment with the appropriate omega-3 fatty acid is even more important for people who have already experienced a heart attack or stroke as studies have demonstrated that these patients are at greater risk for another serious CVD event even if they’re already being treated with a statin.
• While price is certainly an important consideration for many, we always recommend going with the treatment supported by the best evidence-based research. Additionally, patients should be encouraged to carefully follow their physician’s guidance to dispense the product as prescribed that has been proven in large clinical outcome trials.

Although fish oil supplements are among the most widely used supplements in the United States, many consumers do not realize that it is the omega-3 fatty acid that is valuable in these products when it comes to heart health. It is important for people, especially those with heart disease, to read the label for the amount of omega-3 and to consult with their pharmacists if they have questions.

About the Author

For more than 20 years, Dr. Preston Mason has served as a faculty member of the Cardiovascular Division at Brigham and Women’s Hospital and Harvard Medical School in Boston, Massachusetts, USA. Mason is also president and co-founder of Elucida Research, a biotechnology research institute. He has received many awards for his research in cardiovascular pharmacology and teaching over the past 30 years, including an honorary doctorate in science. Mason serves as a consultant for industry including for Amarin, Corp.