Vitamins: are a large group of organic substances with different chemical structures and physiological functions. They are organic substances that are naturally present in food, cannot be synthesized by the body, are required in small amounts, have specific physiological functions, and do not participate in the composition of the body nor do they provide caloric energy. Usually we divide vitamins into two categories: 1) water-soluble vitamins: vitamin C, vitamin B; 2) fat-soluble vitamins: vitamins A, D, E, K, etc. Vitamins (vitamin) are a class of trace organic substances that people and animals need to obtain from food to maintain normal physiological functions, and play an important role in human growth, metabolism and development. If you find yourself or a family member with any of the following conditions or symptoms, you may want to pay attention to the early signs of vitamin deficiency. Vitamin A deficiency: rough and itchy skin, deep white lines on nails, dry hair, memory loss, irritability and insomnia, dry conjunctiva of the eyes, urinary tract stones. More beef liver, eggs, red and yellow vegetables, fruits and cod liver oil should be consumed. Vitamin B1 deficiency: allergy to sound, allergic reaction to sound, intermittent soreness in the lower legs, foot disease, neurodermatitis, etc. Should eat more beans, cereals, hard fruits, fruits, milk and green leafy vegetables. Vitamin B2 deficiency: inflammation of the corners of the mouth, various skin diseases such as dermatitis, scrotum, etc., burning sensation in the hands and limbs, over-sensitive reaction to light, etc. More liver, milk, eggs, beans and green vegetables should be consumed. Vitamin B3 deficiency: thick tongue, puffy lips, sore tongue, sore lips, extra scalp, dry oral mucosa dewlap. More yeast should be consumed. Vitamin B12: Easy to lose balance in movement, intermittent pain in indeterminate position, tingling sensation in fingers and fingers, should eat more animal liver and yeast. Vitamin C deficiency: No objective reasons such as overexertion, rapid environmental changes or other organic diseases, but often feel fatigue, often easy to catch a cold, cough, decreased resistance, gums often bleed, wounds are difficult to heal, deep marks on the tongue, etc.. More tangerines, oranges, grapefruit, red dates, sour dates, etc. should be consumed. The right amount of vitamin intake is important for your health, learn to reasonably supplement your body with the vitamins it needs.