Milk can affect the absorption of iron, so it is usually consumed 1-2 hours apart. Since iron in food needs to be converted into ferrous ions in the digestive tract before it can be absorbed and utilized by the body, and when patients drink milk, ferrous ions in the body will react with calcium and phosphorus salts in the milk to precipitate in the gastrointestinal tract and then combine into insoluble compounds, which will affect the absorption and utilization of iron, so iron is usually not taken with milk. If iron is taken first, you can drink milk after 1 hour because of the fast absorption of iron. If milk is taken first, it takes 2 hours to digest the protein in milk before taking iron because it takes longer to digest in the stomach. Iron should not be taken with food with high calcium and phosphorus content such as milk, but also with high fat food, food containing tannin (such as tea), food containing sodium bicarbonate (such as various beverages, soft drinks, alkaline food), which are not conducive to the absorption of iron. However, vitamin C can reduce the oxidized iron, thus promoting the absorption of iron. At the same time, vitamin C can keep the environment in the small intestine at a certain acidity, so that iron is soluble, in order to facilitate the absorption in the small intestine. Therefore, oral iron can be taken with vitamin C-rich fruits and vegetables and vitamin C tablets to improve the efficacy of iron.