A just-released UK biobank study has done little to overcome continuing confusion over the value of fish oil supplements for heart health. In fact, its clearest ‘conclusion’ lies in its qualifying statement—the bit where it says that the study highlights the need for further research to fully understand the complex relationship between fish oil supplements and the development and progression of different cardiovascular diseases.

The study, published in the BMJ, examined the effects of taking fish oil supplements on the progression of cardiovascular diseases. It looked at how fish oil supplements affected the risk of developing various heart and blood vessel conditions, including atrial fibrillation (irregular heartbeat), major adverse cardiovascular events (like heart attacks and strokes), and death.

The researchers followed a large group of over 415,000 people aged 40-69 years old in the UK Biobank study for about 12 years on average. They found that for people who didn’t have any cardiovascular diseases at the start, regularly taking fish oil supplements was associated with a higher risk of developing atrial fibrillation and stroke.

However, for people who already had a known cardiovascular disease, regularly taking fish oil supplements was linked to a lower risk of progressing from atrial fibrillation to major adverse cardiovascular events, from atrial fibrillation to heart attacks, and from heart failure to death.

Varying effects of supplements

The researchers concluded that fish oil supplements may have different effects depending on a person’s underlying cardiovascular health. For healthy individuals, fish oil supplements may increase the risk of developing certain heart and blood vessel problems. But for those who already have cardiovascular disease, fish oil supplements may help slow down the worsening of their condition and reduce the risk of more severe complications and death.

Of course, there are times when we need to be reminded of the basic facts of whole food living. What makes fish oil supplementation valuable to many is the opportunity to inject a regular dose of omega-3.

Most people eating a healthy plant-based diet have no difficulty getting enough omega-3 into their system. And, as this article from the Physicians Committee website points out, if you include things like walnuts, flaxseed, chia seeds, hemp seeds, edamame, seaweed, and algae, you’ll get all the omega-3 you need.

Some alarming, and mostly unsubstantiated claims are made around the ‘benefits’ of fish oil supplementation. A previous News Bite article published in Whole Food Living’s Spring 23 print edition looked into this.

Researcher Ann Marie Navar expressed concern about the wide range of health claims made about fish oil supplements. Because the claims are so varied, “it’s not surprising to me that my patients think fish oil is helping them,” she said.

Plant-based nutrition guru Dr Michael Greger (nutritionfacts.org) shares this view. In the following video, he goes one step further and warns doctors to stop highly marketed fish oil supplementation in all patients.