We have all heard how omega 3s are good for health, but a lot of the time study findings are over-exaggerated. In this post I summarise the best available evidence showing the benefits of omega 3 supplementation in lowering blood pressure.
Is hypertension such a big issue for health?
So why omega 3s?
Many studies have shown reductions in blood pressure with the use of EPA and DHA, but a lot of these findings are not applicable to the rest of us.
A meta-analysis is a study that looks at multiple studies in one go, analysing the data over many years and summing up all the evidence in one scientific paper. Meta-analyses provide the highest level of scientific evidence, allowing medical professionals to make informed decisions.
This meta-analysis included the data obtained from 70 randomised controlled trials and analysed the effects of EPA and DHA ingestion on systolic and diastolic blood pressure.
Ok, let’s dive straight to the study findings now!
In normotensive subjects, systolic blood pressure significantly decreased by -1.3 mmHg. Because blood pressure tends to increase by around 0.6 mmHg per year in adults, this means that high intakes of EPA and DHA could potentially delay systolic hypertension by over 2 years.
Meanwhile, the effects of EPA and DHA in reducing blood pressure in hypertensive subjects were more pronounced. Systolic blood pressure was reduced by -4.5 mmHg, and diastolic blood pressure by -3.1 mmHg.
Such reductions in blood pressure among hypertensive patients could prevent the need to take blood pressure lowering medications or maintain hypertensive patients at a lower stage of progressive hypertension.
However, please note that the mean daily dose of EPA + DHA that was given patients across all 70 studies was 3.8 g/day, which is quite a LARGE amount!
Yet, doses of EPA + DHA just under 1 g/day, lead to significant reductions in systolic blood pressure of -2.4 mmHg.
In most studies analysed in this meta-analysis, EPA and DHA was given to patients as fish oil. As for the control groups, patients were given other types of oils to consume, such as olive, corn, sunflower oil.
Overall, by lowering blood pressure, EPA and DHA can reduce the risk of cardiovascular events, improving the quality of life in individuals and saving costs to the healthcare system.
Miller, P.E., Van Elswyk, M. & Alexander, D.D. (2014). Long-chain omega-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid and blood pressure: a meta-analysis of randomized controlled trials. American journal of hypertension, 27(7), 885–896.