Turn on the television these days and you’re likely to see ads asking men 45 or older if they might be suffering from something called “Low T.” Do you lack energy (the ads ask)? Have you lost some of your zest for life? Even more alarming—could you be losing your desire for sex altogether? Yikes! It’s Low T! Pass me the cure, whatever it is!

Now, I don’t mean to diminish men’s concerns over their vitality and virility—far from it. But before any of my male acquaintances or readers fall for these ads for drugs to boost their levels of testosterone—for that’s the “T” in Low T—I thought I would look into this question with a little less sensationalism and a little more common sense. And what I found is that while it’s normal for testosterone levels to decline slightly after a man passes age 40, only a small percentage of men have levels below normal for their age. So “Low T” is not inevitable, as some ads make it seem—and the best solution for the vast majority of men is not a drug.

I decided to take a deeper look at the latest research on the subject. I found a recently completed study on testosterone levels in healthy older men done at the University of Sydney that put one myth to rest right off the bat. Researchers in Australia found that while it’s true that men may lose their youthful testosterone levels if they are experiencing declining health, for healthy men, testosterone typically drops only very slightly as a consequence of age. How the study worked…

In two study centers in Australia, researchers drew blood nine times over three months from 325 healthy men age 40 to 97, finding that their levels did not differ significantly among the wide age range—and indicating that age had a minimal effect on testosterone concentrations.

Even the researchers were somewhat surprised by the study results. They concluded that while there may be a modest drop in blood testosterone experienced among older men—and these men at the same time may experience nonspecific symptoms such as easy fatigue and low sexual desire—their symptoms are likely due to mounting chronic and acute conditions associated with aspects of aging that have nothing to do with testosterone levels, for instance heart disease and obesity.

Prior research, in fact, has shown that testosterone drops a small amount—about 1% per year—in healthy men starting as early as age 30, according to Spyros Mezitis, MD, PhD, a clinical endocrinologist at Lenox Hill Hospital in New York City.

However, even by age 65, some studies suggest, testosterone levels will be at levels that would be considered “low-normal” for healthy younger men, Dr. Mezitis told me. Problems such as erectile dysfunction are prone to occur more often in less healthy men with conditions such as diabetes or cardiovascular disease. This means that if a man experiences dramatic symptoms that could be caused by testosterone loss, he should not shrug his shoulders at the weary inevitability of it all. He should check with his doctor about the possibility of an illness of another sort.

Alarming commercials have their place, Dr. Mezitis thinks, if they raise awareness among men about being vigilant about good health. But those who may need help shouldn’t order some nebulous product off the Internet or television—they should visit their doctors and get a blood test to see what their testosterone levels really are and discuss the results with their doctors.

“For the minority of patients who do have testosterone problems,” he said, “we’ll recommend hormone replacement therapy. We don’t prescribe it unless the person is symptomatic and has a genuinely low testosterone level, and we’re sure that his prostate is healthy.” Since testosterone in the form of a gel or a patch can contribute to the growth of prostate tumors, hormone replacement therapy needs to be carefully discussed with your doctor.

Men are notoriously reluctant to step up and be vigilant about overall health. I’m hoping that these reports will reassure them that, for the great majority, their natural testosterone levels can provide the vitality and virility they need for a lifetime. If a man feels fatigued or listless, that’s a very good reason to schedule a checkup with his doctor. Something like depression, hypotension (low blood pressure) or increased abdominal fat may well be the reason for feeling low. Take care of it… and you can move forward with all your usual enthusiasm for life.