Image courtesy of Men's Health

The Best Health Tests

Just because someone plays guitar, that doesn't mean they sound like Jimi Hendrix. Same goes for doctors. Here at Men's Health, we've learned that top doctors--the ones who want to stop problems before they start--tend to do more tests than your average M.D. A lot more.

How come? "Most people think of going to their doctor when they're ill," says Tyler Cooper, M.D., M.P.H., CEO of Cooper Aerobics in Dallas, Texas. "We prefer people come to us when they're not having any problems. That way, we can correct problems early on, when they're easy to treat and before they cause any long-term damage." These exams--most of which are simple blood tests--can help.

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Oral Glucose Tolerance Test

Most doctors test for diabetes by looking at your blood sugar levels after you haven't eaten for 8 hours, called a fasting blood glucose test. Keith Berkowitz, M.D., of the Center for Balanced Health in New York City, does something more realistic. He gives you a sugary drink and then observes how your body responds to it, called an oral glucose tolerance test. "It's a truer representation of your body's function, since most of the day, your body is processing a meal--not fasting," Dr. Berkowitz says. "Your blood sugar levels with this test go up 20 years in advance of what a fasting blood glucose test will show."

Who needs it? Dr. Berkowitz gives one to all of his patients as a screening tool. Make sure you have it by age 30 if you have a family history of diabetes, or if you have heart disease or are at risk for heart disease.

At risk for diabetes? Fill your plate with these 12 Diabetes-Fighting Foods.

Endoscopic Colonoscopy

The American Cancer Society recommends that men have one of four types of colon cancer tests. Ignore that. Have a colonoscopy. It's the best way to detect precancerous polyps smaller than half a centimeter, says Danilo Diaz, M.D., a gastroenterologist in York, Pennsylvania. "The danger is that because colorectal screenings are usually only recommended every 5 to 10 years, if a small cancerous polyp is missed, it can develop into full-blown cancer before the next exam," Dr. Diaz says. "And once colon cancer spreads, the five-year survival rate is extremely low."

Who needs it? If you have zero risk factors, start at age 50 and have one every 10 years, Dr. Diaz recommends. But if a close relative has had colon cancer, start at age 40 or 10 years before he was diagnosed--whichever one comes first.

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Testosterone and Estrogen Blood Test

The sex hormone testosterone is what makes us men. It determines the strength of your erection and the size of your muscles. But over the past two decades, testosterone levels have been in decline, according to a study in the Journal of Clinical Endocrinology and Metabolism. Once you turn 40, your testosterone levels dip by 2 percent each year. Have both testosterone and estrogen measured so your doctor can look at the ratio. (Running on empty? Here are 3 Ways to Boost Your T Levels.)

Who needs it? All men at age 40, yearly thereafter.

Thyroid Stimulating Hormone Blood Test

Your thyroid is a gland that helps regulates the hormones in your body. When it's out of whack, the symptoms can be more random than a Bill Hicks standup routine. If the gland is pumping out too much thyroid hormone, you'll lose weight for no reason, feel nervous or anxious, and have an increased heart rate. Too little thyroid hormone, and it's the opposite: You'll gain weight, feel weak and cold, and want to collapse at your desk from fatigue. "They're abstract symptoms. People might not recognize exactly what they're experiencing, but they'll say they just don't feel the way they want to," Dr. Cooper says. Medication can regulate your levels.

Who needs it? Everyone, at age 30, Dr. Berkowitz says.

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