Tens of millions of Americans are battling thyroid problems – but most of them are losing the war, and they might not even know it.

A new study finds that one of the main drugs used to treat hypothyroidism, aka underactive thyroid, can more than triple the risk of fractures in seniors – and the higher the dose, the greater that risk.

And that means even if your drug is “working,” it could be quietly laying the groundwork for a potentially life-wrecking bone break down the road.

The researchers looked at data on more than 200,000 seniors – mostly women – who were at least 70 years old when they were given levothyroxin, a synthetic version of the thyroid hormone, between April 2002 and March 2007.

Ten percent suffered at least one fracture, and researchers say those on the highest dose of the drug had 3.5 times the risk of those on the lowest, according to the study in BMJ Online First.

And that’s just frightening, because not many conditions can ruin a senior’s life more quickly and completely than a bone break. One recent study even found that hip fractures double the five-year death risk in women and triple it in men.

The researchers behind the new study say docs need to pay careful attention to dosages – and lower the dose, if possible, as time goes on to lower the risk of bone breaks.

But there’s a much easier way, and that’s with natural thyroid hormone – or what should be more accurately called “thyroid hormones,” because there are two: T3 and T4.

The synthetic stuff contains only T4, which has to be converted to T3 by the body – but for many patients, that’s actually part of the problem. They can’t do it, and that makes the synthetic hormone practically useless.

The natural stuff, called desiccated thyroid, contains both T3 and T4 – and that’s why many seniors who make the switch can feel the difference almost immediately.

Don’t expect your typical mainstream doctor to understand or appreciate the difference – to him, thyroid is thyroid.

See an experienced naturopathic physician instead.

I’ve become more than a little embarrassed by my profession as patient after patient has shown up at my office with terrible and persistent pain that was ignored by other physicians.