A study published in the British Medical Journal (BMJ) suggests that regular use of fish oil supplements may be linked to reducing the risk of cardiovascular events such as heart disease and stroke. A team of researchers from China and the US used data from Biobank UK, a large-scale population study based on more than half a million British men and women.
The team analyzed 427,678 men and women between the ages of 40 and 69 who had no cardiovascular disease or cancer, and completed a questionnaire on the use of supplements, including fish oil.
Death certificates and hospital records are used to monitor deaths of any cause (“all-cause mortality”), cardiovascular death and cardiovascular disease events, such as heart attacks and strokes, up to 2018. Thirty-one percent of the subjects reported taking fish oil supplements regularly at the beginning of the study.
The researchers found that fish oil supplements reduced all-cause mortality by 13 percent, reduced cardiovascular disease mortality by 16 percent, and reduced the risk of cardiovascular disease events by 7 percent (388 all-cause deaths per 100,000 people in nine-year median follow-up, 124 cardiovascular deaths, and 295 cardiovascular events).
The association between fish oil use and cardiovascular disease events appeared to be stronger in people with high blood pressure. These beneficial links persist, taking into account traditional risk factors, such as age, gender, lifestyle, diet, medications and other supplements.
The researchers say that habitual use of fish oil reduces the risk of all-cause dying and cardiovascular mortality, and there are several mechanisms to explain these results. For example, omega-3 fatty acid supplements have beneficial effects on blood pressure, cholesterol levels and heart rate, all of which protect the development of cardiovascular disease events.
Despite the large sample size, this is an observational study and therefore the cause cannot be determined. The researchers also point to limitations, such as a lack of information about the dose, duration and side effects of fish oil use.