What to watch with TSH and skin aging?

The relationship between TSH and skin aging is complex. TSH itself is a marker of thyroid function, not a direct driver of skin aging. However, thyroid hormones influence collagen synthesis, cell turnover, and skin hydration. Elevated TSH (hypothyroidism) can lead to dry, coarse skin and reduced elasticity; low TSH (hyperthyroidism) can cause thin, fragile skin. The provided context lacks specific evidence linking TSH variants to skin aging. Genetic tests for TSH-related SNPs (e.g., in TSHR, DIO2) typically have small effect sizes and are not clinically established. More relevant are nutritional factors: iodine, selenium, zinc, and vitamin D support thyroid function. Skin aging is multifactorial (UV, glycation, oxidative stress). Evidence: unclear. Caution against overclaims from commercial tests.