Recently, the topic of #Excessive sun protection# has been hotly discussed again, and some experts believe that excessive sun protection will cause vitamin D deficiency, which may not only lead to osteoporosis, but also may lead to reduced immunity, memory loss, diabetes, and ......
How amazing is vitamin D?
01
What is vitamin D
Vitamin D is an essential fat-soluble vitamin that helps the body absorb calcium from the intestines and is essential for bone growth and strengthening. In addition to this, vitamin D plays a role in regulating a variety of cellular functions in the body.
During the physical examination, doctors usually detect the level of 25-hydroxyvitamin D [25(OH)D] in the blood, which has good stability and is recognized as a reliable indicator to evaluate the nutritional status of vitamin D in the human body, mainly including 25(OH)D2 and 25(OH)D3 two forms, of which 25(OH)D3 is the main form of vitamin D in the blood.
What are the functions of vitamin D?
Maintain bone health
Vitamin D plays a role in promoting the absorption of calcium and phosphorus, two minerals that make up bones. Therefore, adequate intake of vitamin D is essential for maintaining the health and strength of bones.
Insufficient vitamin D intake is closely related to the occurrence of a variety of bone diseases. Vitamin D deficiency increases the risk of osteoporosis and may also lead to osteomalacia, and vitamin D deficiency in childhood can cause rickets, which can lead to growth retardation and skeletal deformities.
Reduces the risk of cardiovascular disease
A 2021 paper investigated the relationship between serum 25(OH)D levels and the risk of cardiovascular disease, and concluded that vitamin D deficiency increases the risk of cardiovascular disease. It is recommended to correct the state of low vitamin D levels to reduce the burden of cardiovascular disease.
Reduce the incidence of cancer
Related studies have found that vitamin D can reduce the incidence of colorectal cancer, lung cancer, breast cancer, prostate cancer and other cancers.
Reduces the risk of Alzheimer's disease and stabilizes mood
Epidemiological studies have shown that vitamin D levels are associated with a person's risk of developing Alzheimer's disease, and although the mechanism is not fully elucidated, it is now widely believed that vitamin D may reduce the risk of Alzheimer's disease by reducing neuroinflammation and vascular damage.
Some studies have also found that depression in the elderly is associated with vitamin D deficiency, suggesting that vitamin D supplementation can regulate mood and improve depressive state.
Prevent autoimmune diseases
A large clinical trial published in the British Medical Journal (BMJ) in 2022 showed that long-term vitamin D supplementation can help prevent autoimmune diseases. Vitamin D is also effective in preventing upper respiratory tract infections and reducing the probability of childhood asthma.
Prevent diabetes
Studies have found that vitamin D supplementation in infancy can reduce the risk of type 1 diabetes, and it is also meaningful for type 2 diabetes, which can improve the body's glucose metabolism, increase insulin sensitivity, and delay the progression of diabetes.
May be beneficial for patients with chronic kidney disease
Some studies have shown to slow the progression of chronic kidney disease, but further research is needed. Vitamin D deficiency is prevalent in patients with chronic kidney disease, and vitamin D status is inversely correlated with the progression of chronic kidney disease, and vitamin D supplementation can slow the progression of chronic kidney disease and reduce the risk of death in kidney dialysis patients.
03
What are the possible conditions for the lack of dimension D?
According to the People's Republic of China Health Industry Standard "Screening Method for Vitamin D Deficiency in the Population", vitamin D deficiency is defined when the level of 25(OH)D in the blood is less than 12 ng/ml.
Source: "Screening Methods for Vitamin D Deficiency in the Population", click to view a larger image
Vitamin D deficiency should be suspected if the following problems are found
Inflammation often occurs, or it is not easy to get better after infection;
Feeling depressed, especially during the winter months;
I always feel tired;
Joint pain, weakness in the limbs, muscle pain.
Vitamin D deficiency is related to environmental and genetic factors, and common influencing factors include: age, skin color, season, geographic latitude, altitude, dress habits, sunshine hours, sun protection measures, dietary habits, air pollution, obesity, and drugs that affect vitamin D metabolism.
04
How to supplement vitamin D?
sunbathe
In the season when the skin of the limbs can be exposed, such as summer, try to obtain vitamin D through sun exposure, and when receiving sun exposure, the limbs are required to be exposed, no sunscreen, no glass, no umbrella, the time selection is ideal between 10:00~14:00, the irradiation time is 5~10 min, and the frequency is 2~3 times a week.
Older people and individuals with darker skin need longer hours of sun exposure.
Eat foods rich in vitamin D
Fatty fish, especially salmon, sardines, tuna, dried mushrooms, egg yolks and offal, can be supplemented with vitamin D in natural foods.
Vitamin D supplementation
Common vitamin D preparations can be used as a bone health supplement. Individual differences and safety should be noted in the clinical application of vitamin D preparations, and blood and urine calcium concentrations should be monitored regularly.
The recommended intake of vitamin D for adults is 400 IU/day, 600 IU/day for the elderly aged 65 and above due to lack of sunlight or intake and absorption disorders, the maximum tolerable intake is 2000 IU/day, and the dose of vitamin D for the prevention and treatment of osteoporosis is 800~1200 IU/day.
If you are deficient in vitamin D, please seek medical attention promptly
It is recommended that people with vitamin D deficiency seek medical attention in time, screen for comorbidities, and follow the doctor's instructions for timely treatment and re-examination. Excessive vitamin D supplementation may lead to elevated urinary calcium, which may increase the risk of kidney stones and renal calcium.
It is comprehensively compiled from "Screening Methods for Vitamin D Deficiency in the Population", "2013 Edition of Dietary Nutrients for Chinese Residents", Guangxi Drug Administration, Western Theater General Hospital, Popular Science China, Life Times, etc