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In their large cohort study (1) Lai and colleagues found that higher blood levels of Omega 3 polyunsaturated fatty acids were associated with a higher likelihood of healthy ageing, and thus, they recommended increasing dietary consumption of seafood in older adults.
However, firstly, the study design does not permit causal interpretation of the results (2), and secondly, any benefits from increased seafood consumption has to be weighed against potential risks to health from microplastic toxicity, in view of widespread marine contamination (3).
1) Lai HTM, de Oliveira Otto MC, Lemaitre RN, et al. Serial circulating omega 3 polyunsaturated fatty acids and healthy ageing among older adults in the Cardiovascular Health Study: prospective cohort study. BMJ. 2018; 363: k4067
2) Zhu Y, Ferrara A, Forman MR. Omega 3 polyunsaturated fatty acids and healthy ageing. BMJ. 2018; 363: k4263.
3) Smith M, Love DC, Rochman CM, Neff RA. Microplastics in Seafood and the Implications for Human Health. Curr Environ Health Rep. 2018; 5: 375-386.