Longitudinal associations between marine omega-3 supplement users and coronary heart disease in a UK population-based cohort

Abstract

ObjectivesAssess the association between marine omega-3 polyunsaturated fatty acid (n-3 PUFA) intake from supplements, mainly cod liver oil, and coronary heart disease (CHD) mortality.DesignProspective cohort study, with three exposure measurements over 22 years.SettingNorfolk-based European Prospective Investigation into Cancer (EPIC-Norfolk, UK).Participants22 035 men and women from the general population, 39–79 years at recruitment.ExposureSupplement use was assessed in three questionnaires (1993–1998; 2002–2004; 2004–2011). Participants were grouped into non-supplement users (NSU), n-3 PUFA supplement users (SU+n3) and non–n-3 PUFA supplement users (SU-n3). Cox regression adjusted for time-point specific variables: age, smoking, prevalent illnesses, body mass index, alcohol consumption, physical activity and season and baseline assessments of sex, social class, education and dietary intake (7-day diet diary).Primary and secondary outcome measuresDuring a median of 19-year follow-up, 1562 CHD deaths were registered for 22 035 included participants.ResultsBaseline supplement use was not associated with CHD mortality, but baseline food and supplement intake of n-3 PUFA was inversely associated with CHD mortality after adjustment for fish consumption. Using time-varying covariate analysis, significant associations were observed for SU+n3 (HR: 0.74, 95% CI 0.66 to 0.84), but not for SU-n3 versus NSU. In further analyses, the association for SU+n3 persisted in those who did not take other supplements (HR: 0.83, 95% CI 0.71 to 0.97). Those who became SU+n3 over time or were consistent SU+n3 versus consistent NSU had a lower hazard of CHD mortality; no association with CHD was observed in those who stopped using n-3 PUFA-containing supplements.ConclusionsRecent use of n-3 PUFA supplements was associated with a lower hazard of CHD mortality in this general population with low fish consumption. Residual confounding cannot be excluded, but the findings observed may be explained by postulated biological mechanisms and the results were specific to SU+n3.

The balance between food and dietary supplements in the general population

“…The confounding associated with SU + EPA/DHA and SU − EPA/DHA as well as the changes over time in supplement use was modelled using time-varying covariates analysis. It was observed that CHD mortality was 26 % lower (95 % CI 16, 34 %) among SU + EPA/DHA compared with NSU, but no significant association was observed when comparing SU − EPA/DHA v. NSU ( 106 ) . Due to the observational nature of the study, residual confounding and colinearity of nutrients could have occurred.…”

Long-chainn-3 fatty acids as an essential link between musculoskeletal and cardio-metabolic health in older adults

“…was the most popular supplement (consumed by 32% of men and 45% of women) (10) . However, it is worth noting that over-the-counter fish oil preparations do not always contain the dose advertised on the label, and that the fatty acids can often be extensively oxidised, compromising their proposed biological function (11,12) .…”

“…While the average oily fish intake falls alarmingly short of this 140 g recommendation, also noteworthy is the median intake for both age groups is 0 g per week, with the majority of UK adults avoiding dietary intake of oily fish altogether. Evidence from the EPIC-Norfolk study highlights that cod liver oil (a source of n -3 PUFA) was the most popular supplement consumed by 32 % of men and 45 % of women (10) . However, it is worth noting that over-the-counter fish oil preparations do not always contain the dose advertised on the label, and that the fatty acids can often be extensively oxidised, compromising their proposed biological function (11,12) .…”

Omega-3 Polyunsaturated Fatty Acids and Cardiovascular Health: A Comprehensive Review

“…39 A 22 year study of > 20,000 patients found that OM3 supplementation was associated with a lower hazard of CHD mortality. 40 The JELIS trial in Japan…”