Bone health is more often mentioned in relation to women's health than men's. But after the age of 30, men's bone mass begins to decline. This can lead to a greater chance of suffering fractures -- and with all those softball game slides and "touch" football tackles, that's not something guys can really afford.
For the most part, bone loss during this decade is minor. However, if you have a family history of osteoporosis, if you smoke or if you tend to hit the sofa instead of the gym, you might want to consider getting a DEXA scan (dual energy X-ray absorptiometry) to measure your bone density. Even if you're not losing bone mass, such a test would provide you with a valuable baseline for future measurements.
To help keep your bones strong and man-sized, you might want to consider taking 1,000 milligrams of calcium combined with 400 IU (international units) of vitamin D, which has been shown to enhance the body's ability to absorb the bone-building nutrient. Weight-bearing exercises (including walking) have also been shown to slow bone loss [source: Liebman].