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Fish oil supplements may improve heart health

Regularly taking fish oil supplements may be linked to a lower risk of death and cardiovascular disease (CVD) events, such as heart attack and stroke, according to an analysis of data from the UK Biobank study, published in The BMJ. The analysis included 427 678 men and women aged 40–69 years who did not have CVD or cancer, were enrolled in the study from 2006 to 2010, and completed a questionnaire on supplements use. Estimates of all‐cause mortality, CVD deaths, and CVD events, such as heart attack and stroke, to 2018 were based upon death certificates and hospital records. At the start of the study, almost one‐third of participants (31%) reported taking regular fish oil supplements. The researchers found that fish oil supplements were associated with 13% lower risk of all‐cause mortality, 16% lower risk of CVD mortality, and 7% lower risk of CVD events (388 fewer all‐cause deaths, 124 fewer CVD deaths, and 295 fewer CVD events per 100 000 people; median follow‐up, 9 years). The association between fish oil use and CVD events was stronger for people with high blood pressure. These favourable associations remained after correcting for traditional risk factors, such as age, sex, lifestyle, diet, medications, and other supplement use. Mechanisms that could explain the findings include the fact that omega‐3 fatty acid supplements have known benefits for blood pressure, cholesterol levels, and heart rate, all of which would reduce the likelihood of CVD events. Despite the large sample size, this observational study cannot establish causation, and the lack of information on the dosage, duration, and side effects of fish oil use limit their interpretation.

https://www.bmj.com/content/368/bmj.m456

Moderate egg intake not associated with increased cardiovascular disease risk

A study published by The BMJ adds to evidence that moderate egg consumption (one egg per day) is not associated with increased cardiovascular disease (CVD) risk. To evaluate the effect of egg consumption on CVD risk, diet and lifestyle factors must be repeatedly assessed over an extended period, and the effect of eggs on CVD risk in the context of other animal and plant‐based foods considered. US researchers investigated the link between egg intake and CVD (non‐fatal heart attack, fatal coronary heart disease, and stroke) by analysing repeated measures of diet over as long as 32 years, starting from 1980. Their findings are based on data from three large cohort studies — the Nurses’ Health Study (NHS), the NHS II, and the Health Professionals’ Follow‐Up Study (HPFS) — that respectively included 83 349 female nurses aged 30–55 years, 90 214 female nurses aged 25–44 years, and 42 055 male health professionals aged 40–75 years, all free of CVD, type 2 diabetes, and cancer at the start of the study. During the follow‐up period, there were 14 806 cases of CVD, including 9010 of coronary heart disease and 5903 of stroke. Most people ate one to five eggs per week; those with a higher intake had a higher mean body mass index and greater red meat consumption, and a smaller proportion was being treated with statins. After adjusting for age, lifestyle and dietary factors, no association was found between egg intake and risk of CVD. The estimated risk of CVD was higher when the researchers statistically replaced one whole egg a day with one serving of processed red meat (15%), unprocessed meat (10%) or full fat milk (11%), but not with fish, poultry, legumes, cheese, or nuts. An updated meta‐analysis of 28 observational studies further supported the overall lack of an association between egg intake and CVD risk. However, in contrast to US and European studies, moderate egg consumption was associated with a slightly lower CVD risk in Asian studies, perhaps because eggs are included in a variety of Asian dishes, whereas in Western countries eggs are often eaten with red and processed meats and refined grains. As an observational study, causation could not be established, and findings regarding health professionals may not be reflective of the general population.

https://www.bmj.com/content/368/bmj.m513