Everyone should make sure they get enough of these two nutrients, but especially women and others at risk for osteoporosis. Attention to diet and exercise are important not only for treatment, but also for prevention. Calcium intake is critical, and those who need it the most, younger women and girls don't get enough. But calcium alone can't build bone. Without vitamin D, calcium isn't sufficiently absorbed.
Most people get enough vitamin D because skin produces it in sunlight.
But people confined indoors who have a poor diet, which includes many older Americans or who live in northern latitudes in winter may be deficient. A lifelong habit of weightbearing exercise, such as walking or biking, also helps build and maintain strong bone. The greatest benefit for older people is that physical fitness reduces the risk of fracture, because better balance, muscle strength, and agility make falls less likely. Exercise also provides many other life-enhancing psychological and cardiovascular benefits. Increased activity can aid nutrition, too, because it boosts appetite, which is often reduced in older people.