Thyroid-stimulating hormone levels vary significantly over the course of a day
the verdict
SUPPORTED
the evidence backs this
confidence 80/100
Thyroid-stimulating hormone (TSH) levels exhibit robust, statistically significant diurnal variation over the course of a day, typically peaking overnight and reaching lower levels in the afternoon.
Evidence for · 4
Effect of goitrogen administration on the circadian rhythm of serum thyroid stimulating hormone in the rat
1981 · cited by 5
Demonstrates a significant diurnal rhythm of serum TSH in animal models independent of peripheral thyroid hormones.
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More for · 3
Diurnal fluctuations in thyroid hormones - the Bispebjerg study of diurnal variations.
2026 · cited by 0
Shows statistically significant diurnal variation of TSH in humans, peaking at 2 AM and varying substantially over 24 hours.
Chronotherapeutic optimization of radioactive iodine therapy in differentiated thyroid cancer: The rationale for evening administration.
2025 · cited by 0
Highlights the circadian rhythm of TSH, which peaks overnight and is relevant for clinical treatment timing.
PBK Modeling of Thyroid Hormone Circadian Rhythm: Elucidating Thyroidal and Extrathyroidal Contributions to Thyroid Hormone Chronobiology
2025 · cited by 0
Describes the robust circadian pattern and daily oscillations of TSH regulated by the hypothalamic-pituitary-thyroid axis.