You know you can’t stand when your bones are weak. Your mobility is impaired. That’s why they say the skeleton is the foundation of the body.Bone-thinning osteoporosis is a disease that causes your bones to become thin and weak and increases the risk of breaking a bone.Dr Alex Buteera, an orthopedic surgeon at Rwanda Military Hospital, says a healthy bone is strong, and "when it becomes weak we call it osteoporosis.” "The best way to manage it is prevention. Your genes decide your potential height and bone strength.  Three factors are responsible for keeping bones healthy throughout life: adequate amount of calcium, adequate vitamin D and regular exercise,” says Dr Buteera. To maintain healthy or strong bones, Dr Buteera advises, calcium is obtained from dairy products like milk, yoghurt, dark green leafy vegetables, fish, soya and fortified cereals or supplements. "The vitamin D obtained from sunlight, about 10 minutes twice a day is enough. Other sources are eggs, milk and oily fish. Supplements are also available”, he says.Exercises should be regular and involve strength training and weight bearing like walking, jogging, running, climbing, and weight lifting, he adds. "It is best done early in life to build a reserve but there is no need to worry. If you follow the above you will be healthy.” "The most vulnerable are frail patients who are house bound, pregnant, or breast-feeding mothers and post-menopausal. These need the above and sometimes use vitamin and mineral supplements,” Dr Buteera says. Boosting bone strengthThe Harvard Health Publications says the best prevention for bone-thinning osteoporosis begins early—during the first two decades of life, when you can most influence your peak bone mass by getting enough calcium and vitamin D and doing bone-strengthening exercise. If you are over age 20, it is said, there’s no need to be discouraged. It’s never too late to adopt bone-preserving habits. If you are a man younger than 65 or a premenopausal woman, these strategies can help you shore up bone strength as a hedge against developing osteoporosis.Monitor your diet. Get enough calcium and vitamin D, ideally through the foods you eat. Although dairy products may be the richest sources of calcium, many foods, such as orange juice are calcium-fortified. Fruits, vegetables, and grains provide other minerals crucial to bone health, such as magnesium and phosphorus.Maintain a reasonable weight. This is particularly important for women. Menstrual periods often stop in women who are underweight—due to a poor diet or excessive exercise—and that usually means that estrogen levels are too low to support bone growth.Don’t smoke and limit alcohol intake. Smoking and too much alcohol both decrease bone mass.