Thyroid Autoimmunity is Associated with Dietary Fat Consumption

Dietary factors are crucial in the onset and development of autoimmune thyroid disease (AITD), but the relationship between specific fatty acids and AITD remains unexplored.

We analyzed the US National Health and Nutrition Examination Survey 2007 to 2012 data on 3949 men and 3964 women aged 20 years and over with valid data on antithyroid peroxidase antibodies (TPOAb), antithyroglobulin antibodies (TgAb), and details of fat intake using multivariable regression models to examine the relationship of fat intake and specific fatty acid intake with thyroid autoimmunity.

Of the 7913 participants, 7.5% had TgAb seropositivity and 11.9% had TPOAb seropositivity. The seropositivity of TgAb and TPOAb was more common in low-fat intake participants. In the overall population and men, fats were associated with thyroid autoimmunity before and after full adjustment for age, ethnicity, body mass index, smoking status, and urine iodine concentration [total fat: odds ratio (OR) = 0.64, 95% confidence interval (CI): 0.49-0.83; saturated fatty acid: OR = 0.65, 95% CI: 0.51-0.84; monounsaturated fatty acid: OR = 0.65, 95% CI: 0.50-0.85; polyunsaturated fatty acid: OR = 0.76, 95% CI: 0.57-0.995, after full adjustment in men]. Some specific fatty acids followed a similar pattern. The association between fats and TgAb seropositivity was significant in the overall population and men. The association between fats and TPOAb seropositivity was only found in the overall population.

We found a strong association between fat consumption and thyroid autoimmunity in the overall population and men from the nationally representative population-based survey. Fat and fatty acid consumption may be of benefit to individuals with thyroid autoimmunity.