BMD is an important marker of bone quality, reflecting the degree of osteoporosis and predicting the risk of fracture. Due to the increasing improvement of the measurement test article and the development of advanced software, the method can be used at different sites and the accuracy of the measurement is significantly improved. In addition to diagnosing osteoporosis, it can also be used for clinical pharmacological observation and epidemiological investigation, and has significant superiority in predicting osteoporotic fractures. 1.Single photon absorptiometry (SPA): Using the principle that the absorption of radioactive substances by bone tissue is proportional to the bone mineral content, the bone mineral content of human extremity bones is measured by radioisotope elimination. The site generally chosen is the junction of the radius and the middle and distal 1/3 of the ulna (middle and lower 1/3 of the forearm) as the measurement point. Generally right-handed people measure the left forearm, and “left-handed” people measure the right forearm. This method is used more often in China, and the equipment is simple, inexpensive and suitable for epidemiological census. The method can not determine the bone density of the hip bone and the median bone (vertebrae). 2, dual-energy X-ray absorptiometry (DEXA): through the X-ray tube ball after a certain device to obtain two kinds of energy, that is, low-energy and high-energy photon peak. After this photon peak penetrates the body, the scanning system sends the received signal to the computer for data processing and derives the bone mineral content. The instrument can measure the amount of bone in any part of the body with high accuracy and less harm to the human body. The radiation dose for detecting one part is equivalent to 1/30 of a chest film and 1% of QCT. There is no problem of radioactive source decay, and it has been gradually carried out in major cities in China with good prospects. 3.Quantitative CT (QCT): In the past 20 years, computerized machine layer (CT) has been widely used in the field of clinical radiology. qCT can accurately select specific parts of the bone to measure bone mineral density, and can evaluate the bone mineral density of cortical bone and spongy bone respectively. Clinical fractures caused by osteoporosis are often located in areas rich in spongy bone such as the spine, femoral neck and distal radius, and the use of QCT can observe bone mineral changes in these areas, which are currently only used in research work due to the large amount of X-rays received by the subjects. 4, ultrasonic measurement method: due to its non-radiation and more sensitive diagnosis of fracture and has attracted widespread attention, the use of acoustic conduction velocity and amplitude attenuation can reflect the amount of bone mineral content and bone structure and bone strength, and DEXA correlation is good. The method is easy to operate, safe and harmless, inexpensive, and the instrument used is ultrasonic bone densitometer. According to the different reasons for the lack of bone density and the mechanism of action, different raw materials can be selected in the design of health food formulations. Often used raw materials are as follows: 1, calcium such as calcium absorption is normal, daily to 1, 00 grams – 1, 50 grams can be. Among various calcium supplements, calcium carbonate is more commonly used. For the elderly over 65 years old 0, 75 grams – 2, 5 grams per day. For those who use estrogen with many side effects and the possibility of inducing endometrial cancer, giving large doses of calcium can play the same role as using estrogen, and patients with kidney stones cannot consume large amounts of calcium. 2, vitamin D and its active products in the past that elderly patients with osteoporosis are often accompanied by vitamin D deficiency, and therefore advocate more vitamin D. In fact, except for the combination of osteochondrosis (generally speaking, only children are susceptible to osteochondrosis, such as rickets), intestinal calcium absorption disorders and vitamin D metabolite production reduction, generally do not need to supplement a large amount of vitamin D, indeed, the above three conditions, can be given at the same time Vitamin D. 3, calcitonin calcitonin can reduce bone resorption, reduce the calcium in the blood circulation and increase the calcium content in the bone, calcitonin because it can reduce blood calcium, so in the use of calcitonin should be supplemented with adequate amounts of calcium, to play a role in the treatment of osteoporosis. 4, phosphates phosphates for the treatment of osteoporosis has been developed in recent years, phosphate can promote bone formation, inhibit the destruction of bone cells, can be long-term application. 5, other currently, the market to increase bone density of the main raw materials of health food to chemical raw materials and Chinese medicine extracts, taking the dosage form mainly capsules, tablets, etc.. After the introduction of the new regulations of health food, the technical requirements of health food research and development will be improved. According to the declared health care function, the boundaries of raw materials can be relaxed, and some new raw materials can be used, and some new dosage forms can be developed, which will better improve the effect of health food.