Meds to boost thyroid production

DEAR DOCTOR: I have been taking levothyroxine for an underactive thyroid for about 40 years (I’m 74). I have progressed from 0.025 milligrams to 100 milligrams currently. I recently read an article indicating that long-term use of this drug increases the incidence of bone fractures by about 80 percent. What alternative treatments are available?

DEAR READER: I can understand your worry about thyroid hormone and an increased risk of fractures, especially after being on the medication for 40 years. People with hyperthyroidism

(an excess of thyroid production) have a greater risk for osteoporosis, and studies have found that thyroid hormone increases bone resorption while interfering with calcium me tabolism within the bone.

In fact, people with hyperthyroidism have a 10 to 20 percent decrease in bone density compared to people with normal thyroid levels; they also have an increased risk of fracture. The impact of taking thyroid hormone to keep your levels normal is less clear. So far, it appears to depend on where in the normal range you end up.

In a 2017 study, the authors found that those with the lowest range of thyroid stimulating hormone, or TSH, (0.45- 0.99 mIU/ L) had a 24 percent increased risk of hip fracture compared to those with the highest range ( 3.5- 4.49 mIU/ L). The study also found that higher levels of T4 were associated with an increased risk of fractures, a finding that has been corroborated in studies in both Europe and Taiwan.

Keep in mind that the studies have been of relatively short duration, so it’s difficult to know how taking thyroid hormone may have affected you specifically.

I would try to take the lowest possible dose of thyroid hormone required to keep your thyroid levels on the lower end of normal. You should also make sure you walk and do weight-bearing exercises to help decrease your risk of osteoporosis.

Supplements that promise to naturally boost thyroid hormone production are not reliable options. Stick with medications proven to work — and at the lowest possible level.