Ask-the-Expert Q&A with Dr. Penny Kris-Etherton: New Data Reinforces the Effectiveness of Lipids for Heart Health

A heart-to-heart about omega-3s and cardiovascular health

• A new study including almost half a million individuals links regular fish oil intake to lower risk of premature death and cardiovascular disease (CVD) endpoints, including heart attacks and strokes.
• The latest research is consistent with the generally positive findings reported by existing studies on the benefits of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) omega-3s on cardiovascular health.
• In our latest Ask-the-Expert interview, Professor Penny Kris-Etherton – a distinguished specialist in cardiovascular nutrition - discusses the significance of these new findings and how R&D professionals can help to guard heart health through omega-3 innovation.

Many nutritionists recommend fish oil supplements for individuals who consume little to no fish or seafood because their diet is low in omega-3 fatty acids. However, the effectiveness of omega-3s in supporting our health – specifically our heart health – has sometimes been debated. This lack of consensus is largely due to inconclusive data reported in some recent clinical trials. In this interview we speak to Dr. Penny Kris-Etherton, a distinguished Professor of Nutrition at Penn State University’s College of Health and Human Development, about the latest scientific findings supporting the link between omega-3 nutrition and cardiovascular health.

You can also hear Dr. Penny Kris-Etherton talk at the NUTRITION2020 online satellite symposium “Making sense of omega-3 headlines: Recent evidence on cardiovascular outcomes and public health implications”. 

Please could you talk us through the findings of this new research?

Dr Penny Kris-Etherton: Thank you for inviting me to discuss this topic with you! A nine-year study that followed almost half a million individuals, of which nearly a third regularly consumed fish oil supplements, reported that eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) positively impact several important cardiovascular outcomes¹. In the recently published results, the research concluded that omega-3 fish oil supplements were associated with a 13% lower risk of death, 16% reduced risk of dying from CVD and 7% lower risk of a CVD event, such as stroke or heart attack. Analysis of the data confirmed that the observed benefits were independent of factors such as age, sex, lifestyle habits, diet, medication and other supplement use. However, it is not known whether the positive outcomes were a direct result of omega-3 nutrition or if other factors related to the individual’s diet and lifestyle contributed.

Based on those results, why in your opinion is this study so important?

Dr Penny Kris-Etherton: Based on evidence linking EPA and DHA omega-3 fatty acids to reduced risk of CVD, several authoritative statements have been issued by regulatory agencies and scientific societies that recommend the inclusion of these nutrients in the diet. However, the ambiguous results reported by some recent clinical trials has led to some confusion about omega-3 benefits for heart health.

Publication of clinical trials – ASCEND and VITAL – between 2018 and 2019 greatly increased the body of evidence available on omega-3s and heart health.^2,3 The focus of both studies was to identify the effects of omega-3 fatty acids in people with diabetes and the link between omega-3 fatty acids and the risk of major cardiovascular events in individuals with no prior illness, respectively. Although both studies showed null results in the primary outcomes, they did find significant results in the secondary outcomes associated with cardiovascular disease, including substantial risk reductions in heart attack and fatal heart attack in the VITAL trial. In addition, the primary outcome was statistically significant in the half of the population with weekly fish consumption below the median level of intake. The recent REDUCE-IT study on the other hand, showed positive primary and secondary outcomes in individuals with existing CVD and taking statins.⁴ Unlike the ASCEND and VITAL studies, where the omega-3 dose was provided in the nutritional range, the REDUCE-IT trial explored the benefits of omega-3 at a pharmaceutical dose of 4 g/d EPA (as Icosapent Ethyl).

Additionally, a recent Cochrane analysis, which included the results of 86 randomized controlled trials and more than 160,000 individuals, found some positive findings but concluded that increasing EPA and DHA levels had little or no effect on mortality or cardiovascular health.⁵ In an updated meta-analysis, which combined the data from 13 studies researching omega-3 supplementation and CVD, a positive link between marine omega-3 supplementation and CVD was reported, even after exclusion of the REDUCE-IT study (as it applied an EPA dose in the pharmaceutical range).⁶ The 2019 analysis also highlighted that risk reduction was linearly related to omega-3 dosage for total CVD and major vascular events.

Where some studies have produced inconclusive or ambiguous results, it’s important to consider the impact that factors such as an inadequate dose or duration of omega-3 supplementation, inconsistencies in the methodology and interaction with other medications may have on the clinical outcomes. In addition, in the larger clinical trials, composite primary endpoints were used that include stroke risk, which has not typically been affected by omega-3 supplementation. This may have decreased the sensitivity to detect a more robust effect in one or more of the other components of the composite, e.g. heart attacks or cardiac death.

This new observational study is therefore important because it confirms the positive findings found in previous trials and adds to the database of evidence indicating the effectiveness of fish oil supplementation for cardiovascular health.

Can you explain how omega-3 exerts its benefits on heart health?

Dr Penny Kris-Etherton: Several mechanisms may explain the benefits of omega-3 fatty acids on cardiovascular health. The omega-3 fatty acids contained in fish oil are thought to have a positive effect on blood pressure⁷, plasma triglycerides⁸ and heart rate⁹, all of which exert a protective role against CVD. Additional studies have demonstrated that omega-3 helps to improve flow mediated arterial dilatation^10,11, i.e. the widening of an artery when blood flow increases through it, and also possess anti-arrhythmic properties that may be clinically beneficial. However, omega-3s are also well-known for their anti-inflammatory properties¹² and may therefore have a preventative role by impacting the physiological processes associated with CVD risk.^13,14 Further research is required to help identify all of the mechanisms (beyond the ones described) by which omega-3s exert their effects on cardiovascular health.

Does this study change the advice already given to consumers?

Dr Penny Kris-Etherton: In short, no. Despite the scientific evidence and expert advice, many adults worldwide do not meet the recommended daily dose of 250-500 mg of EPA and DHA. In fact, a recent study of NCCA Division 1 athletes found that 95% of those tested did not meet the recommended intake of omega-3 EPA and DHA.¹⁵ This demonstrates a clear opportunity to boost intake for optimal heart health.

Nutrition experts, including dsm-firmenich, advise consumers to increase their omega-3 fatty acids intake by eating fish at least twice a week as part of a balanced diet. However, if this is not possible due to dietary preferences or lack of resources, dietary supplements containing omega-3 fatty acids can be an efficient and cost-effective way to fill nutritional gaps and help individuals to achieve optimal omega-3 levels. If an individual is at risk of CVD, it is important that they consult a medical professional regarding the best nutritional and pharmacological intervention for their specific requirements.

So, if dietary supplements are a good option, why is omega-3 status still low in many populations worldwide? Do you think the nutrition industry could do more to encourage individuals to consume omega-3?

Dr Penny Kris-Etherton: Firstly, it’s important to remember that most nutritionists would encourage individuals to follow a balanced diet, including at least two portions of fish a week to meet the recommended omega-3 intake. But dietary supplements help consumers to meet appropriate levels when this is not feasible. However, despite most consumers saying they are aware of omega-3 supplements, compliance is still low when it comes to dietary supplement intake. There are a number of common barriers to consumption including the large size of pills and capsules making them harder to swallow, the have a fishy smell or aftertaste associated with fish oil as well as the lack of awareness of inadequate omega-3 intake and unclear labelling.

Discover omega-3s for a new generation

To address evolving consumption preferences of consumers globally, and at the same time meet their evolving nutritional needs, continued innovation in omega-3 product format and application is essential. dsm-firmenich is committed to continued consumer research and awareness of emerging trends – such as the shift towards plant-based diets – in order to develop tailored solutions that meet consumer preferences. Such innovations will ultimately contribute to improved omega-3 intake, promoting the health and wellbeing of global populations throughout their lives. To support the growing global population in achieving the optimal health benefits from omega-3s, dsm-firmenich is also committed to further advancing its understanding about the relationship of omega-3 intake and risk of CVD, and other chronic diseases, to help establish accurate dietary reference values (DRVs).

In addition to the well-established benefits of omega-3s for cardiovascular, brain and visual health, there are a wider range of science-backed benefits provided by omega-3s that tap into topical consumer health concerns including immunity, active living, mind and sleep. In addition, in order to attract a new generation of consumer, omega-3 dietary supplement manufacturers need to meet the demand for more sustainable, plant-based alternatives.

As the only commercially available omega-3 of plant origin that combines significant levels of EPA and DHA in a single source, life’s™OMEGA is a unique solution that allows dietary supplement manufacturers to develop effective and safe omega-3 solutions, all while meeting rising consumer demand for more sustainably-sourced products.