(HealthDay News) — Higher dietary intake of an omega-3 fatty acid found in nuts, seeds, and plant oils is associated with a lower risk for mortality, according to a study published online Oct. 14 in The BMJ.
Sina Naghshi, from Tehran University of Medical Sciences in Iran, and colleagues conducted a systematic literature review and meta-analysis to examine associations of dietary intake and tissue biomarkers of alpha linolenic acid (ALA) with the risk for mortality.
Based on data from 41 prospective cohort studies (1,197,564 participants), the researchers found that high intake of ALA was significantly associated with a lower risk for deaths from all causes (pooled relative risk [RR], 0.90), cardiovascular disease (CVD) death (pooled RR, 0.92), and coronary heart disease (CHD) death (pooled RR, 0.89), as well as a slightly higher risk for cancer mortality (pooled RR, 1.06) versus low intake. A 1-g/day increase in ALA intake (equivalent to one tablespoon of canola oil or 0.5 ounces of walnut) was associated with a 5% lower risk for all-cause (pooled RR, 0.95) and CVD mortality (pooled RR, 0.95). Higher blood levels of ALA were associated with a reduced risk for all-cause and CHD mortality only.
“Further studies should examine the association between ALA and a wider range of causes of death to provide a more comprehensive assessment of the potential health effects of ALA as well as to examine whether specific foods rich in ALA are differentially associated with mortality from cancer and other causes,” the authors write.