Abstract：There are limitations in observational epidemiological studies when exploring the relationships between polyunsaturated fatty acids（PUFAs）and risk of diseases. Recent years have seen Mendelian randomization（MR）being widely employed in etiology research,since it can avoid bias caused by confounding factors and reverse causality in observational epidemiological studies. With the development of PUFAs related genome-wide association studies,MR study design and statistical Methods,MR studies have been conducted to investigate the relationships of PUFAs and risk of diseases including cancer and autoimmune disease. We systematically reviewed the published literature of MR studies on the association between PUFAs and risk of diseases,so as to discuss the underlying advantages and disadvantages of MR studies and to provide clues for further understanding the role of PUFAs in health and disease.
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