Phoenix City Zhou Zhiyi The elderly and vitamin D

Phoenix City Zhou Zhiyi The elderly and vitamin D (The author Zhou Zhiyi is a former lecturer of internal medicine at Guangzhou Sun Yat-sen Medical University) In the recently published "European Clinical...

Phoenix Zhou Zhiyi The elderly and vitamin D (The author Zhou Zhiyi is a former lecturer of internal medicine at Guangzhou Sun Yat-sen Medical University) In the recently published "European Clinical Nutrition" magazine, a research report from Oregon State University in the United States was published. This research report shows that elderly people with low vitamin levels have at least a 30% increased risk of death than those with high vitamin levels. What is even more noteworthy is the elderly with low vitamin D levels and frailty. The mortality rate is three times higher than that of normal elderly people. This result was obtained by researchers through a survey of 4,300 elderly people over the age of 60. Regarding such a result, medical scientists realize that screening vitamin D levels in the elderly, understanding and improving their vitamin D levels, is of great significance in reducing the mortality of the elderly and extending their life span. Surveys have found that about 1 billion people around the world have insufficient vitamin D levels. Vitamin D deficiency and insufficiency is an increasingly serious global problem. The latest research in the United States shows that more than 90% of people of color and 75% of white people are vitamin D deficient. Recently, a survey in Shanghai showed that there is widespread vitamin D deficiency and insufficiency among Shanghai residents, regardless of their age, whether they are male or female. They tested the serum 25?#32671; vitamin D-3 levels of 452 healthy adults and found that 88.9% of men and 90.7% of women had vitamin D deficiency and insufficiency. Some scholars have also reported that the incidence of vitamin D deficiency among postmenopausal women in Thailand and Malaysia is 50%. In Japan and South Korea, due to their high latitudes, the incidence of vitamin D deficiency is as high as 90%. Everyone already knows that elderly men and postmenopausal middle-aged and elderly women are generally at risk of osteoporosis. The occurrence of osteoporosis is not only related to calcium intake, but also closely related to the level of vitamin D in the body. Now, research from various countries around the world has shown that vitamin D deficiency is also closely related to cardiovascular and cerebrovascular diseases, hypertension, diabetes, autoimmune diseases (such as rheumatoid), multiple sclerosis and malignant tumors. Doctors' research on vitamin D has now expanded from bones to a wider range of systemic functions. More and more evidence shows that adequate vitamin D intake may play an important role in the prevention and treatment of chronic diseases. The extraskeletal effects of vitamin D have attracted widespread attention. The main source of vitamin D for humans is sunlight exposure, followed by food intake. There is a substance called 7-deoxycholesterol in human skin. When it is exposed to ultraviolet rays, it can be converted into vitamin D-3. Vitamin D-3 in the skin is transported to the liver through the blood stream for conversion, and then transported to the kidneys and monocyte giant cell system, and finally becomes biologically active vitamin D. The process of synthesizing vitamin D in human skin is mainly carried out in summer when the sun is strong, while in winter and spring it is mainly the vitamin D reserve in animals. This is especially true for people living in high-definition areas. This also shows that the level of vitamin D in the human body has obvious seasonal fluctuations, with the highest level in autumn and the lowest in spring. At that time, from a theoretical point of view, adults could get the vitamin D they needed by exposing their faces and hands to the sun for 2 hours a week, or babies wearing diapers and being exposed to the sun for 30 minutes a week. Scholars believe that 80-90% of the vitamin D needed by the human body comes from ultraviolet rays from the sun, and vitamin D intake from food should not exceed 20% of the total requirement. Sources of vitamin D in food are very limited. Regular consumption of fatty sea fish can provide a certain amount of vitamin D-3. Some yeast-fermented foods and mushrooms, which are derived from plants, also contain small amounts of vitamin D-2. As for the so-called "chemical foods" that add a certain amount of vitamin D during the preparation process, such as milk, juice, bread and vegetable butter, they can also provide a certain amount of vitamin D. For the elderly, vitamin D deficiency often occurs due to the decline in physical strength, the reduction in outdoor activities, the decline in digestion and absorption capabilities, and the year-by-year decline in the ability to synthesize vitamin D through sunlight exposure. In recent years, with the continuous deepening of research on the relationship between vitamin D and health, medical scientists and relevant medical organizations around the world have gained new understandings of the research, evaluation, treatment and prevention of vitamin D deficiency. It is now believed that the normal level of vitamin D in the human body should be between 30-100ng/ml. Since the amount of vitamin D ingested through food is very limited, moderate sunlight exposure is very important for improving the nutritional status of vitamin D. It is worth pointing out that vitamin D synthesized through sunlight exposure to the skin is self-limiting and will not cause an overdose of vitamin D. Scholars point out that due to urban air and particulate pollution, human skin color (such as dark skin), human clothing coverage and climate (such as winter), the vitamin D absorbed by the human body through exposure to sunlight has been reduced. From the analysis of the vitamin D levels of the population, in order to meet the body's demand for vitamin D, especially for the elderly, pregnant women and children, it is necessary to take and supplement a certain amount of vitamin D. The American Medical Association proposed a new daily intake of vitamin D in 2010. The recommended daily intake for seniors over 50-70 years old is 600 to 800IU (international units), and the maximum intake can reach 4,000IU per day. Of course, vitamin D poisoning is also rare, and its symptoms include poor appetite, nausea and vomiting, constipation, weakness, dizziness and weight loss. Scholars believe that for the elderly, daily supplementation of 1,000 or 2,000 IU of vitamin D is necessary, and generally there will be no side effects of overdose and poisoning. At the same time, vitamin D supplementation can also be adjusted based on the level of vitamin D detected in the blood.