Men, there are two main conditions that can cause your testosterone levels to plunge. One's completely within your control... one's completely out of it.

They're extra pounds and extra years, and you can take a big hit from either one. And if you're tacking on both at the same time, you'll end up feeling like half the man you used to be -- even if you're twice the size.

Some 900 overweight prediabetic men were assigned to either the diabetes drug metformin, a placebo, or a weight-loss regimen for a year. Those who got the drugs and placebo saw no changes in their hormone levels.

But half of the men with low testosterone who lost weight saw their levels rise -- with a drop of 17 pounds leading to an average testosterone boost of 15 percent.

Hey, better than nothing at all and if you're overweight you need to lose the pounds anyway. But 15 percent isn't enough to stoke your internal fires.

It's barely enough to light a match.

The men in the study who had low testosterone were at or below 300 nanograms per deciliter, which means a 15 percent increase would put them at a maximum of 345 nanograms per deciliter.

For normal male function, by comparison, you need between 500 and 1,000 nanograms per deciliter.

Sure, you could lose more than 17 pounds, but that's not the entire answer here. Like I said, age takes a toll of its own, and there's no "treatment" for that (the party every year is nice, though).

Visit a naturopathic physician experienced in natural hormone supplementation. He can check your levels, top you off and monitor your progress. I recommend a doctor who belongs to the American College for Advancement in Medicine.