Doc: Does too much vitamin D cause bone mass reduction?

Dear Dr. Roach: I’m 70, Caucasian, slim and was diagnosed with osteoporosis five years ago. Before that, I took Fosamax for five years. I take 1,000 mg calcium citrate, 3 mg boron and a multivitamin containing 2,000 IU vitamin D. An X-ray showed three compression fractured vertebra. I read that taking more than 1,000 IU of vitamin D can cause bone mass loss! I started crying thinking that I caused the fractures from taking too much vitamin D. I’ve stopped the multivitamin and just take 500 IU of the vitamin D. I’m outside an hour a day. Do you know of bone mass loss from too much?

V.W.

Dear V.W.: Low levels of vitamin D are a common and treatable cause of bone loss, which can lead to fractures. It’s a good idea to check the vitamin D level in people with known osteoporosis. There remains controversy about the optimum level of vitamin D, but a level between 30 and 50 ng/mL is generally considered safe.

Very high levels of vitamin D can cause calcium to come out of bones, and can cause risk of kidney stones, as well as symptoms. However, this is almost unheard of in a dose less than 4,000 units daily. It is very unlikely that you were taking too much vitamin D, so there’s no need to blame yourself.

Although people with boron deficiency are at higher bone loss risk, using boron as part of osteoporosis treatment has never shown to reduce fracture rates. I don’t recommend boron supplementation. Leafy green vegetables like spinach and kale are good sources in the diet.

Dear Dr. Roach: I have mandibular tori. What in the world got this started? Was it medication or something catching, like from the dentist?

I.L.

Dear I.L.: The mandible is the lower jaw, and a torus is a bony growth. They usually are present on both sides, so they are called tori. A torus also can be present on the hard palate. They may grow slowly over time.

It’s not clear where they come from, but they are more common in men and in people who grind their teeth, so they are thought to arise from stress in the bone. They are of no concern and do not need to be treated unless they are bothering you.

Email questions to ToYourGoodHealth@med.cornell.edu.