Couple of Weekly Portions of Oily Fish Can Help Ward off Strokes

19th October 2012

Eating at least two servings of oily fish a week is moderately but significantly associated with a reduced risk of stroke, finds a study published in the British Medical Journal.

Regular consumption of fish and long chain omega 3 fatty acids has been linked with a reduced risk of coronary heart disease and current guidelines recommend eating at least two portions of fish a week, preferably oily fish like mackerel and sardines. But evidence supporting a similar benefit for strokes remained unclear until an international team of researchers, analysed the results of 38 studies to help clarify the association between fish consumption and risk of stroke or mini-stroke (transient ischaemic attack or TIA). Collectively, these conditions are known as cerebrovascular disease. 

After adjusting for several risk factors, participants eating two to four servings a week had a moderate but significant 6% lower risk of cerebrovascular disease compared with those eating one or fewer servings of fish a week, while participants eating five or more servings a week had a 12% lower risk. An increment of two servings per week of any fish was associated with a 4% reduced risk of cerebrovascular disease. In contrast, levels of omega 3 fats in the blood and fish oil supplements were not significantly associated with a reduced risk.

Several reasons could explain the beneficial impact of eating fish on vascular health. For example, it may be due to interactions between a wide range of nutrients, like vitamins and essential amino acids, commonly found in fish. Alternatively, eating more fish may lead to a reduction in other foods, like red meat, that are detrimental to vascular health. Or higher fish intake may simply be an indicator of a generally healthier diet or higher socioeconomic status, both associated with better vascular health.

Although there’s a possibility that some other unmeasured (confounding) factor may explain their results, the authors concluded that the study reinforced “a potentially modest beneficial role of fish intake in the cause of cerebrovascular disease”.

Chowdhury R et al. Association between fish consumption, long chain omega 3 fatty acids, and risk of cerebrovascular disease: systematic review and meta-analysis. BMJ 2012;345:e6698

Categories: Nutritional News, Metabolic Health