You can't eat too many vitamins. If a large amount of vitamin C is taken orally, nausea and vomiting will occur. If you take a large amount of vitamin C for a long time, it can reduce the absorption of vitamin B 12 in the intestine, thus aggravating the condition of megaloblastic anemia, leading to a sharp increase in uric acid and gout.

If you take tens of thousands of units of vitamin A every day (for example, the concentration ratio of vitamin A and D in a cod liver oil is 10: 1, and the dosage is above 10 drops, and the amount of vitamin A is too large), poisoning symptoms may occur in a few months. The early symptoms are irritability and loss of appetite, and later there will be bone pain in limbs, headache, vomiting, anterior fontanel uplift, dry hair, broken lips, hepatosplenomegaly and so on.

Children who are sensitive to vitamin D poisoning may take vitamin D4000 international units every day (the concentration ratio of vitamin A and D is about 25 drops of concentrated cod liver oil 10: 1), and symptoms of poisoning may occur after 1 ~ 3 months. The earliest symptoms are anorexia, even anorexia, irritability, crying and low fever. Without careful analysis, it is easy to be misdiagnosed as vitamin D deficiency (called "calcium deficiency"). Gradually, children will suffer from drinking too much, frequent urination, nocturia and other conditions that affect their functions, such as renal failure and heart murmur, because bones, kidneys and blood vessels have corresponding calcification.