Dietary Fats May Protect Against Thyroid Autoimmunity

TOPLINE:

Higher consumption of total fat, saturated fatty acids, monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs) is linked to a lower risk for thyroid autoimmunity in men.

METHODOLOGY:

• Studies suggest fatty acids have a positive effect on autoimmune diseases, but data on the relationship between autoimmune thyroid disease and specific fatty acids are lacking.
• Researchers examined the association between thyroid autoimmunity and different fatty acids using data from the US National Health and Nutrition Examination Survey (2007-2012), involving 7913 adults (age ≥ 20 years; 50% men).
• Thyroid autoimmunity was defined as antithyroid peroxidase antibody (TPOAb) and antithyroglobulin antibody (TgAb) levels above the reference limits, with a seropositivity of 11.9% and 7.5%, respectively, among participants.
• Dietary fat intake was measured by one or the average of two 24-hour dietary recall interviews and categorized into total fat, saturated fatty acids, MUFAs, PUFAs, and specific fatty acids.
• The study included adjustments for confounders such as age, race, ethnicity, body mass index, smoking status, and urinary iodine concentrations.

TAKEAWAY:

• Participants with a lower fat intake, including total fat, saturated fatty acids, MUFAs, and PUFAs (P = .002), were more likely to show TgAb seropositivity.
• A higher prevalence of TPOAb seropositivity was noted in those with a lower fat intake, including total fat, saturated fatty acids, and MUFAs, but not PUFAs.
• The association between the consumption of dietary fats and thyroid autoimmunity was significant overall and in men but not in women; in men: Total fat (adjusted odds ratio [aOR], 0.64; 95% CI, 0.49-0.83), total saturated fatty acids (aOR, 0.65; 95% CI, 0.51-0.84), total MUFAs (aOR, 0.65; 95% CI, 0.50-0.85), and total PUFAs (aOR, 0.76; 95% CI, 0.57-0.995).
• In men, but not women, significant inverse associations were found between thyroid autoimmunity and some specific saturated fatty acids (octanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, and octadecanoic acid), as well as some specific MUFAs (hexadecenoic acid and octadecenoic acid).

IN PRACTICE:

“Our study findings suggest that [lower] dietary fatty acid intake was significantly associated with thyroid autoimmunity. This may help prevent people with early autoimmunity from developing into AITD [autoimmune thyroid disease], which is diagnosed by symptoms of thyroid dysfunction and findings of ultrasound,” the authors wrote.

SOURCE:

This study was led by Lulian Xu and Zhenzhen Liu, Department of Pediatric Endocrinology, Affiliated Children’s Hospital of Jiangnan University (Wuxi Children’s Hospital), Wuxi, China. It was published online in The Journal of Clinical Endocrinology & Metabolism.

LIMITATIONS:

The study’s cross-sectional design limited the ability to establish causality between dietary fat intake and thyroid autoimmunity. The lack of a thyroid-stimulating hormone receptor antibody analysis may have limited the comprehensiveness of the assessment for thyroid autoimmunity. Thyroid autoimmunity is more common in women, but the lower intake of fatty acids in women vs men may have resulted in a less pronounced protective effect.

DISCLOSURES:

The authors Xu and Liu reported receiving funding from the Maternal and Child Health Research Project of Wuxi Health Commission. The authors declared no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.