Vitamin A deficiency is caused by chronic vitamin A deficiency and refers to all the effects of vitamin A deficiency on growth, immunity, embryogenesis, other body systems and survival related. Vitamin A deficiency is recognized by WHO as one of the four major nutritional deficiencies in the world, with a ≥50% morbidity and mortality rate in children with severe vitamin A deficiency, and pregnant women and children are susceptible to vitamin A deficiency. Vitamin A deficiency can be caused by the following conditions: poor diet, digestive disorders, wasting disease, hypothyroidism, diabetes, and zinc deficiency. The best way to prevent vitamin A deficiency in the general population is to eat foods rich in vitamin A. Vitamin A is a fat-soluble vitamin. Vitamin A is a fat-soluble vitamin that occurs naturally only in animal foods, and carotenoids from plants enter the body and can be converted in the liver to vitamin A. Because of the high rate of absorption of vitamin A in animal foods, WHO recommends that at least 40% of the daily supply of vitamin A should come directly from animal foods. In animal food, the highest vitamin A content is liver, sheep liver and beef liver contain about 50,000 IU of vitamin A per 100 g. Milk, butter, cheese and eggs have a medium content of vitamin A. Beef, lamb and pork have a low content of vitamin A. Plant foods are rich in vitamin A-like vitamins. Vegetables or fruits in plant foods rich in vitamin A-like vitamins include pumpkin, carrots, dark green leafy vegetables, potatoes, mangoes, apricots and tomatoes. For infants, breast milk is a better source of vitamin A. Exclusive breastfeeding should be strongly promoted for up to 6 months after birth and continued until 2 years of age, and mothers themselves should eat more vitamin A-rich foods.