We often don't think about our bones particularly when we are young and healthy. However, the strength of our bones as we grow older depends on how we care for our bones even in childhood.

Osteoporosis is the thinning of our bones making us susceptible to fracture. Most people think of osteoporosis as a condition of the elderly. Since bone health starts in childhood, the risk of developing osteoporosis can be a result of decisions made in those early years. Osteoporosis can be a consequence of poor nutrition and physical inactivity from a lifetime of poor habits. Women stop building bone density or thickness between ages 30-35 years. So, it is vital that through childhood and young adulthood females get adequate calcium and exercise to build the foundation for healthy strong bones to last them their lifetime.

Our bodies depend on diet for the calcium needed for strong bones. Some foods are good sources of calcium while other foods contain none. (See the chart from the International Osteoporosis Foundation for sources of calcium.) Specifically, dairy products, leafy dark greens, and beans are all good sources of calcium.

It is important to develop healthy eating habits early in childhood so the child receives adequate nutrition and is more likely to maintain these habits later in life. Steering children away from soda and replacing it with milk or calcium fortified orange juice is a simple way to help children early on to receive bone building calcium. The Center for Disease Control and Prevention recommends calcium intake based on age. (See chart are listed below.)

Good nutrition is not the only factor that plays a role for healthy, strong bones. Weight bearing exercise is necessary for building and maintaining bone strength because this type of exercise stresses bone which makes it stronger. Additionally, research shows that regular exercise can help prevent bone loss. Examples of exercise that help build bone are walking, jogging, running, weight lifting, dancing, tennis, racquetball, soccer, and climbing stairs. Although swimming and bicycling are great forms of exercise for cardiac health, they do not help the body maintain bone strength.

Timothy Lohman, a physiology professor at the University of Arizona studied the effect of calcium and exercise on bone density. His research shows that 20-25 minutes a day of weight bearing or resistance exercise plus age appropriate calcium intake can increase bone density 1-2 percent. This can result in a reduction of fracture risk by 8-15%. Of course, another benefit of regular exercise is weight reduction and management. After 20 minutes of exercise, the body starts to burn fat. So any exercise over 20 minutes is a bonus to help lose excess weight or maintain a healthy weight.

Calcium Content of Common Foods

• Non-fat Milk: 1 cup, 300 mg calcium

• Nonfat Yogurt: 1 cup, 490 mg calcium

• Swiss Cheese: 1 oz., 270 mg calcium

• Mozzarella, part skim: 1 oz., 210 mg calcium

• American Cheese: 1 oz., 140 mg calcium

• Cottage Cheese: 1 cup, 160 mg calcium

• Parmesan Cheese, grated: 2 T, 140 mg calcium

• Pudding: prepared 1/2 cup, 150 mg

• Frozen Yogurt: 1 cup, 200 mg

• Ice Cream, light: 1/2 cup, 200 mg

• Black Beans: 1 cup, 120 mg calcium

• Navy Beans: 1 cup, 130 mg calcium

• Fortified Cereal: 1 cup, 300 mg calcium

• Soybeans, cooked: 1 cup, 180 mg calcium

• Spinach, cooked: 1/2 cup, 130 mg calcium

• Broccoli: 1 cup, 90 mg calcium

• Corn Tortilla: 1, 6 inch, 50 mg calcium

• Fortified Orange Juice: 1 cup, 300 mg calcium

• Fortified Cereal: 1 cup, 300 mg

• Waffle, fortified: 150 mg

• Soy milk, fortified: 1 cup, 400 mg

• Tofu: 1 cup, 40 mg

• Almonds: 2 oz., 150 mg

Needed Amount by Age

• Birth–6 months: 210 mg/day

• 6 months–1 year: 270 mg/day

• 1–3: 500 mg/day

• 4–8: 800 mg/day

• 9–13: 1300 mg/day

• 14–18: 1300 mg/day

• 19–30: 1000 mg/day

• 31–50: 1000 mg/day

• 51–70: 1200 mg/day

• 70 or older: 1200 mg/day