Vitamin D3 and Hypothyroidsm

Dear Ask The Doctor: I have hypothyroidism and want to know if I can take a supplement of vitdmin d3

Dear Barb: Yes, you can indeed, and it is recommended for you to do so.

Many articles have been published these last 20 years  showing that persons with hypothyroidism have low levels of vitamin D. This may lead to some bone problems related to hypothyroidism. Maybe due to: 1) poor absorption of vitamin D from the intestine or 2) the body may not activate vitamin D effectively (cholecalciferol (vitamin D2), found mainly in plants and ergocalciferol (vitamin D3), found mainly in animals). Both of these hormones are referred to as vitamin D, and they can either be obtained in two ways: 1)  by exposure of the skin to the ultraviolet (UV) rays of sunlight or 2) from dietary intake. Vitamin D itself is inactive and needs to get converted to the liver to 25-hydroxy vitamin D (25-OH vitamin D) and then in the kidney to 1, 25-hydroxy vitamin D. It is only the 1, 25-OH vitamin D which is biologically active. The Recommended Daily Intake (RDI) of Vitamin D3, due to its high safety profile, may be up  to 10,000 IU per day and because of the wide role it plays in our health, consuming 2,000 to 4,000 IU per day of this vitamin when sunlight is scarce is a prudent way to improve overall health. Also,1,000 to 2,000 IU of Vitamin D3 per day is necessary to reduce the risk of colorectal cancer and that lower doses of Vitamin D3 did not have the same protective effect.