Part of the reason does include better blood testing and the definition of hypothyroidism changing. American Endocrine Society has adjusted the bounds of the am

Part of the reason does include better blood testing and the definition of hypothyroidism changing. American Endocrine Society has adjusted the bounds of the amount of T4 present in the blood upwards throughout the years, increasing the number of people who are affected by hypothyroidism with no meaningful change to the population.