After entering middle age, the loss of calcium in the body gradually increases, for example, women entering menopause and men after 60 years of age, the loss of calcium in the body is more rapid, thus leading to osteoporosis and a significant increase in the incidence of fractures. So how to prevent osteoporosis? There are three aspects: 1, supplement calcium and the right amount of vitamin D3; 2, frequent sun exposure, to ensure that not less than 15 minutes a day (refers to the outdoor); 3, regular exercise. One of these three aspects is indispensable. For calcium supplementation, many middle-aged and elderly people think that 2 annual infusions of calcium gluconate and then several intramuscular injections of vitamin D can achieve the purpose, is this really the case? We first understand the following aspects: 1, calcium absorption and metabolism in the body: the human body daily intake of calcium from food is 300-1500mg, while the human intestinal calcium absorption rate varies greatly, between 20%-70%, with the age of the largest, calcium absorption rate will be reduced. And the absorption of calcium is mainly in the intestine. Calcium is excreted mainly through feces, urine and sweat. If adequate calcium is not available in the diet, the body needs to mobilize bone calcium supplementation into the blood to maintain blood calcium stability and meet physiological needs by bone calcium absorption. The best source of calcium in food is milk and other dairy products with high absorption rate. If there are 2-3 times a day calcium-containing dairy products (such as 250ml milk, 1 slice of cheese or 1 can of yogurt) in the diet, it can basically meet the calcium needs of children and adults; other foods that contain more calcium are green vegetables (such as kale, cabbage and amaranth), shrimp, nuts (such as almonds and beans), soy products, etc., but these Calcium absorption rate in the intestinal tract are low. 2, affect the absorption of calcium food: food vitamin D, protein, sodium, oxalate, caffeine, strong tea, fiber and other substances will affect the absorption of calcium. (1) Vitamin D can enhance the absorption of calcium, its sources are skin synthesis by ultraviolet radiation and food (including vegetables, mushrooms and cod liver oil, egg yolk, etc.) to obtain, under normal circumstances most normal people can synthesize sufficient vitamin D through the skin to meet the needs of the body. However, in winter, northern residents, especially the elderly, seldom go outdoors, so the vitamin D content in the body is reduced and needs to be obtained from diet or even drugs. (2) Excessive intake of protein, sodium, crude fiber will affect the absorption of calcium, oxalate, phosphate, strong tea, coffee will affect the absorption of calcium. (3) Calcium medication: Normal adults need 800-1000mg of calcium per day, children, pregnant women, lactating women, menopausal women and men over 60 years of age need 1200-1500mg of calcium per day. The maximum amount should not exceed 2000 mg. If you do not get enough calcium from food daily, you will need to supplement your calcium deficiency with medication every day. If daily supplementation is needed, of course oral medication is much more convenient than other routes (such as injections). So what kind of calcium is good to take orally? Overseas reports show that the absorption rate of calcium from calcium carbonate, calcium gluconate, calcium lactate, calcium acetate and milk is 31% -39%. Calcium taken orally is absorbed mainly in the small intestine. Calcium from bone powder, marine life shells and other sources, generally high in heavy metals, is not desirable; in addition, different types of calcium supplements contain different amounts of elemental calcium, including calcium carbonate contains more calcium, 40%, calcium gluconate, calcium acetate, calcium lactate contains 9.3%, 25%, 13%, respectively. Therefore, the elemental calcium content of certain calcium products is only a few tens of milligrams, so if you take five hundred milligrams of calcium a day, you need to take a large amount, which will not only affect the absorption of calcium, but also increase the side effects. Some people taking calcium supplements will experience symptoms such as bloating, and taking an increased dose will definitely increase the side effects. In order to reduce side effects, it is recommended to take it once a day, one hour before going to bed at night, so that taking it can also increase intestinal absorption. In summary, calcium injections twice a year do not achieve the purpose of calcium supplementation, and dairy products are one of the best sources of calcium supplementation. The elderly may have difficulty in obtaining adequate calcium from food alone due to intake problems, appetite problems, or other drug effects, and need calcium supplements, which are best used in oral formulations and contain high calcium elements; for those who cannot have adequate vitamin D intake and production, calcium supplements containing vitamin D or supplementation with calcium supplements need to be supplemented with vitamin D. In addition, attention should be paid to the dietary The effects of protein, sodium, oxalic acid, phosphoric acid, strong tea and caffeine on calcium should also be noted. If you have other diseases such as kidney stones, you should take calcium supplements as prescribed by your doctor. To prevent osteoporosis, calcium supplements need to be accompanied by sun exposure and exercise.