There are five phenomena in your body that you may be deficient in vitamin D.

Vitamin D is an important nutrient that can lead to cartilage. British nutritionist Kim Pearson says there are five signs of vitamin D deficiency that need to be looked out for.
first, often appear inflammation or infection after inflammation is not easy to be good. Vitamin D plays a key role in the normal functioning of the immune system, and if lacking, immune cells cannot respond adequately to bacterial invasion, making the body vulnerable to germs.
second, feeling depressed, especially in winter. "Vitamin D plays a key role in maintaining normal levels of serotonin in the brain, a neurotransmitter in the brain, and a lack of serotonin is associated with depression," Pearson told health care information site Healthista.
third, always feel tired. "Vitamin D is extremely important for converting food into energy, and a lack of it may mean that you don't absorb nutrients from food," Pearson said.
fourth, joint pain, weak limbs. According to Pearson, the basic role of vitamin D is to maintain the stability of calcium and phosphorus levels in the body, which is important for the health of joints, muscles and teeth.
fifth, feeling muscle pain. The muscles are all over the vitamin D receptor, Pearson said, and "the overall feeling of muscle pain is often the first sign of vitamin D deficiency."
Xinhua News Agency's micro-special report.