Association between dietary onion intake and subclinical hypothyroidism in adults: a population-based study from an iodine-replete area

Abstract

Background & AimsThe protective effect of onion against thyroid hypofunction has been reported in animal studies. However, in humans, the association between onion consumption and subclinical hypothyroidism are unclear. The study sought to explore the association between habitual onion intake and subclinical hypothyroidism among adult population from an iodine-replete area. ObjectiveWe aimed to investigate the relationship between dietary onion intake and subclinical hypothyroidism in Chinese population MethodsA cross-sectional study (6,515 men and 5,290 women) was performed in Tianjin, China. Frequency of onion consumption was assessed using a valid self-administered food frequency questionnaire. Serum free triiodothyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH) were determined by chemiluminescence immunoassay. Subclinical hypothyroidism was diagnosed with TSH >4.78 IU/mL.Multiple logistic regression was used to evaluate the association of onion intake with subclinical hypothyroidism. ResultsThe prevalence of subclinical hypothyroidism was 2.56% in men and 7.18% in women, respectively. In women, the fully adjusted odds ratios [95% con dence interval (CI)] of having subclinical hypothyroidism across increasing frequency of onion intake were 1.00 (reference) for <1 time/week, 0.99 (0.74-1.34) for 1-3 times/week, 0.73 (0.53-1.01) for 4-6 times/week, and 0.66 (0.46-0.95) for ≥7times/week (P for trend <0.01). However, we observed no signi cant association between onion intake and subclinical hypothyroidism in men. Strati ed analyses suggested a potential effect modi cation by age; the odds ratios (95% CI) across extreme quartiles was 0.43 (0.20, 0.87) in <40 women and 1.05 (0.49, 2.28) in >60 women. ConclusionsFrequent consumption of onion is inversely associated with subclinical hypothyroidism in adult women from an iodine-replete area. Further studies are needed to explore the casual relationship.

Association between thyroid dysfunction, metabolic disturbances, and clinical symptoms in first-episode, untreated Chinese patients with major depressive disorder: Undirected and Bayesian network analyses

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Helicobacter pylori infection increase the risk of subclinical hyperthyroidism in middle-aged and elderly women independent of dietary factors: Results from the Tianjin chronic low-grade systemic inflammation and health cohort study in China

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The longitudinal association between onion consumption and risk of depressive symptoms: results from the TCLSIH Cohort study and the UK Biobank

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