Science: What is low bone density?

What is low bone density? Bone mineral density test is an important basis for judging bone quality, which can reflect the degree of osteoporosis and prevent fracture. If the detection is found to be low, attention should be paid to improving. So what causes low bone density? Let's take a look.

First, how to see the bone density test results?

1. T value is the number of standard deviation (SD) higher (+) or lower (-) than bone mineral density (BMD) obtained by examination compared with the BMD of normal young people, which is the most meaningful value for the diagnosis of osteoporosis.

2. The Z-value is the value obtained by comparing the BMD measured by the examination with the BMD of the normal age group. Although the Z-value is of little significance in the diagnosis of osteoporosis, it can reflect the severity of osteoporosis.

Second, the cause of low bone density?

Low bone density is indeed a phenomenon of calcium deficiency, suggesting that calcium deficiency in the past, whether calcium deficiency at present, can not be generalized. When the human body takes in less than 600 mg of calcium per day, especially children, pregnant women, nursing mothers, the elderly, who need more calcium than the general population, bones and teeth not only do not get calcium supplements, but also use the calcium to maintain daily physiological needs, resulting in reduced bone density. It is important to note that calcium is no longer absorbed into bones and teeth in the general population after about 30 years of age.

Women are more likely to lose bone mass because estrogen in women's blood fluctuates and decreases with the menstrual cycle, and decreases more sharply after menopause. Premature menopause or amenorrhea in women, surgical removal of ovaries, etc., can accelerate bone loss. A lack of testosterone in the blood of men can also increase bone loss. Nutritional deficiency, such as insufficient calcium intake, is also an important cause of bone loss, and women fail to supplement enough calcium in time during pregnancy and lactation, which can cause bone loss of 8%-10%. In addition, often do not exercise, long-term bed, less sunshine, excessive addiction to tobacco and alcohol, etc., can promote bone loss.

Third, low bone density how to do?

Loss of bone mineral density, or bone mass loss, occurs unconsciously with age, women can lose more than half of their bone mass, and men can lose 30% to 40% of their bone mass. Estrogen plays an important role in preventing bone loss and delaying bone aging.

With the loss of bone mass, the bone structure becomes sparse and porous, and it is easy to fracture. Fractures seriously affect people's quality of life, even life-threatening, such as femoral neck fracture within 1 year of death of 20% to 25%, about two-thirds of the surviving patients can not walk, life can not take care of themselves. Therefore, bone loss and osteoporosis should be prevented as soon as possible. Therefore, for people with low bone mineral density, if it is under the age of 30, although the blood calcium is in the normal reference range, calcium-rich foods should also be appropriately increased, in addition to maintaining normal physiological needs, but also to make up for previous losses. Attention to calcium intake is a key measure. Children should consume enough calcium, should ensure more than 800 mg per day, adults need calcium 1000 ~ 1500 mg per day, pregnancy and breastfeeding women should appropriately increase calcium intake. The diet of our residents is based on plant foods, and calcium intake by diet alone is far from meeting the needs of the human body, and appropriate calcium supplements should be added. In addition, we should take an active part in sports. Sunlight can make the skin synthesize vitamin D, promote the absorption of calcium in the small intestine, and reduce bone loss. Therefore, sports activities are best done outdoors.