Metformin linked to lower hypothyroidism

In a random sample of nearly 1000 South African patients with type 2 diabetes the overall prevalence of hypothyroidism was 12%.

Except for black women, the proportion of subjects with hypothyroidism was lower among those taking metformin than those not taking the drug.

Among the women, about one-third not taking metformin had hypothyroidism compared with 20% taking metformin and 3.1% for those who developed hypothyroidism after starting metformin.

For the men, it was 10% for those not taking metformin, 5% for those