Many men suffer from low libido, difficulty concentrating, depression, unusual weight gain and constant fatigue. While these symptoms may be caused by any number of physical or psychological illnesses, one distinct possibility is low testosterone—a lack of one of the body’s most important hormones. More importantly, low testosterone can affect our lives anywhere from their 20s to their 60s.

Yet, unless a doctor is told about the symptoms, they won’t automatically know that low testosterone is the problem. “It’s an under-evaluated issue, because many men—especially older ones—don’t want to complain about these things,” explains Dr. Mahmud Kara, a former specialist with the Cleveland Clinic who now focuses on his line of natural remedies. “Checking for testosterone levels isn’t part of a standard blood test. So, if we don’t know to look for it, we won’t. And the danger is you don’t want to hit the point of irreversibility. For example, seriously low testosterone is directly related to the occurrence or reoccurrence of prostate cancer.”

Indeed, even when drug therapy is required, changes in both lifestyle—including more exercise—and diet can also help reverse the condition or at least raise “T” levels, say experts. First and foremost, getting enough sleep—preferably eight hours a night—is vital. “When we don’t get enough sleep, our levels of cortisol, which is our stress hormone, rise. And it’s cortisol that suppresses the production of T,” says Dr. Gillian Goddard of Park Avenue Endocrinology, in New York City. “Once we get a good night’s sleep regularly, our cortisol levels fall and the body can begin producing T again.”

Not being overweight also makes a big difference, adds Goddard. “Fat makes an enzyme that coverts T to estrogen. And while men need some estrogen, particularly for bone health, if a man has too much fat, the body will convert too much T to estrogen, as well as lower its overall T levels.”

Actual changes in diet, other than avoiding foods that cause weight gain, aren’t usually the answer. “Some foods may help, but you would normally have to eat so much of them it’s really not practical,” says Goddard. “We do know that soy products such as tofu, edamame and soy sauce can theoretically raise estrogen and suppress T production, so we may recommend adding that to a diet. And above all, we stress avoiding alcohol, as it definitely suppresses T production.”

As is often the case, vitamins and natural supplements play a big part in the solution. John J. Accursio, a 30-year-old, Manhattan-based lawyer who was diagnosed with low T a few years back, swears by Roman Testosterone Daily Supplements, which include zinc, magnesium, vitamin D3, ashwagandha, maca and copper. But if supplements are taken, make sure that they don’t have ingredients that can exacerbate, rather than help, the condition.

With so many men now expected to live into or even past their 90s, getting this condition diagnosed once symptoms first appear is paramount, stresses Kara. “Our bodies were not built for the 21st century, so the need to take care of ourselves as well as we can—and for as long as possible—is more important than ever before.”

Brian Scott Lipton is a New York-based journalist who specializes in entertainment, fashion, food and healthcare.