Biotin before a thyroid test: a multivitamin's 30 mcg has not been reported to interfere. A 10,000 mcg gummy is 10 mg — the case-report amount.

TSH normal range in the elderly is not what your lab prints: in women the upper limit rises from 4.0 mIU/L at 50 to 6.0 by 90, while free T4 barely moves.

TSH targets before pregnancy split women into two groups, and only one needs to
be under 2.5 mU/L. The 2026 guideline explains which is which.

TSH levels in pregnancy are read on a different scale. When mildly raised results were rechecked at about three weeks, only 41% were still raised.

The normal TSH range by age is not what your lab used. In NHANES data, 70% of older adults with a TSH above 4.5 sat within their age-specific range.

TSH reference ranges differ because assay platforms can vary by up to 50%, and each lab picks its own reference population. Neither report is wrong.

A subclinical hypothyroidism TSH of 5 or 6 is not overt disease. Treatment is standard at 10; below it, a repeat test comes before a prescription.

A low TSH usually points to an overactive thyroid, which affects about 1 in 100 Americans aged 12 and older. The rest of your report decides which kind.

A high TSH is one of the most common flagged results on a routine panel — nearly 5 in 100 Americans aged 12 and older have an underactive thyroid.

TSH levels by age are not one range. Under current intervals, subclinical hypothyroidism is found in 2.4% of people in their twenties and 5.9% past 70.