I recently had blood work done because I have been very fatigued and have experienced a real loss of energy. My Vitamin D level was 17.8 and my Free T4 was .49. My TSH (thyroid stimulating hormone) was in the normal range of 2.09. My doctor put me on a Vitamin D supplement. Will the Vitamin D make my thyroid level go back up, and do you think I should be on thyroid medication? My doctor says that I should get my blood work done in two months and see how it is then.


The free T4 is below the normal range, but the numbers can vary due to many reasons and your TSH was within the normal range. You need to have another check of the free T4 and TSH in about a month and if it still shows that your free T4 and free T3 are low with a low-normal TSH, and you are having symptoms related to low thyroid hormone level, that would indicate that you have secondary hypothyroidism. You would need further investigation to uncover the cause of it and you may need thyroid replacement. However, since the thyroid hormone levels can be affected so easily and rapidly due to various reasons, it’s best to recheck your levels before committing to an expensive work up and life long thyroid replacement, especially if you are not having any symptoms.

You also need adequate Vitamin D levels in your body to have an efficiency of the thyroid hormone as it is important for the final metabolic step of the thyroid hormone, which takes place at the site where thyroid hormone actually works, inside the nucleus of the cell.

All My Best,
Speaking of Women's Health Nurse

August 31, 2011 at 9:33am