Gaining weight, fatigue, lethargy...may be caused by a lack of this vitamin

Audit expert: Wang Xuejiang

Professor of Pathophysiology, Capital Medical University

If you are an obese person, you have been controlling your diet and exercising enough, but still can't lose weight? It may be that your body is lacking in vitamins!

Some doctors point out that especially for people over 35 years old, their metabolism may begin to slow down and their body fat may increase. They can try to supplement some vitamins related to fat burning and body metabolism, such as vitamin D. This will help avoid fat accumulation, speed up metabolism, and promote the discharge of oil and toxic substances.

Vitamin D deficiency is common

Vitamin D deficiency can be divided into two levels: insufficiency and deficiency. To put it bluntly, insufficiency means a little deficiency, and deficiency means a bit too much deficiency, which must be supplemented quickly.

Vitamin D insufficiency and deficiency are common all over the world - approximately 30% to 60% of children and adults worldwide suffer from vitamin D insufficiency and deficiency; the vitamin D deficiency rate in European countries is 6.9% to 81.8%; a foreign study found that 36% of pregnant women are vitamin D deficient.

According to the "2015-2017 China Residents Nutrition and Health Status Monitoring Report", the serum vitamin D deficiency rate among children and adolescents aged 6 to 17 in my country is 18.6%; in 2015, the serum vitamin D deficiency rate among people aged ≥18 in China was 21.4%; the serum vitamin D deficiency rate among males was 16.1%, and that among females was 26.8%.

Vitamin D is a "health all-rounder". Vitamin D is closely related to the health of people of all ages. In addition to strengthening bones and affecting metabolism, it also brings the following benefits to the body:

Protect your heart and brain

Vitamin D can regulate blood pressure, improve heart function, and reduce the risk of heart disease and stroke. Sufficient intake of vitamin D can reduce the risk of premature death in patients with cardiovascular disease.

Improved mood

Women with moderate to severe depression have seen improvements after taking vitamin D supplements, possibly because vitamin D improves serotonin levels, which are important for improving sleep and bringing about feelings of well-being.

Protecting mother and baby

Mothers with lower vitamin D levels during pregnancy are more likely to have pre-eclampsia, premature birth and low birth weight babies, and have a higher chance of having a caesarean section.

Children whose mothers lack vitamin D are more likely to suffer from respiratory diseases such as asthma and have a higher obesity rate. Vitamin D supplementation can reduce asthma and respiratory infections.

Preventing diabetes

The latest epidemiological studies show that the higher the level of vitamin D in the blood, the lower the risk of diabetes, because vitamin D can stimulate the body to produce more insulin.

How to supplement vitamin D?

1. The most effective method: sunbathing

About 90% of the vitamin D needed by the human body is synthesized in the skin. Generally speaking, half an hour of sun exposure every day can meet the body's need for vitamin D.

There are also requirements for sunbathing:

Generally, preventing it can be achieved by exposing your face and upper arms to sunlight for 5 to 30 minutes between 11:00 and 15:00, three times a week in spring, summer, and autumn.

When you are in the sun, you need to let your skin come into direct contact with the sun more often. Wearing a sunscreen mask, gloves, or holding an umbrella will reduce the effect. Applying sunscreen is also not good. SPF15 sunscreen can prevent 99% of vitamin D synthesis in the skin!

You can also sunbathe under the shade of trees. The scattered ultraviolet rays can help synthesize vitamin D, but you need to increase the time you stay there accordingly.

Sunlight through glass cannot synthesize vitamin D in the skin, so it is basically useless for supplementing vitamin D.

2. Methods with limited effects: dietary supplements

Although dietary supplements feel natural and healthy, the effect of dietary supplements of vitamin D is really very limited. Because the content of vitamin D in natural foods is very limited, if you want to eat enough vitamin D, the total calorie intake may seriously exceed the standard, and the daily food intake is difficult to fully meet the body's demand for vitamin D.

Image source: "Expert Consensus on Evaluation and Improvement of Vitamin D Nutritional Status"

3. Vitamin D supplements

If there is no condition to get enough sun exposure every day and the effect of dietary supplements is limited, you can supplement or prevent vitamin D by taking oral vitamin D supplements.

For ordinary adults, it is recommended to take 400 IU of vitamin D supplements every day. Children, the elderly, pregnant women, and obese people may need more supplements, and it is recommended to determine the supplement dosage under the guidance of a doctor. After being exposed to the sun, the ability of the skin of the elderly over 70 years old to synthesize vitamin D is only 1/4 of that of young people, so it is recommended that older people use vitamin D preparations for supplementation.