Oranges About 1 hour before and after drinking milk, it is not advisable to eat oranges. This is because once the protein in milk meets the fructic acid in oranges, coagulation will occur, thus affecting the digestion and absorption of milk, and other acidic fruits should not be consumed during this time period. Sugar The lysine contained in milk can react with fructose under heating conditions to produce toxic fructosyl lysine, which is harmful to the human body. Do not add sugar to fresh milk while it is boiling, and it is not too late to add sugar after the milk has cooled a bit. The acidity of milk is below 4.6, a large amount of casein will agglomerate and precipitate, which is difficult to digest and absorb, and may lead to indigestion or diarrhea in serious cases. Therefore, it is not advisable to add acidic beverages such as fruit juices to milk. Chocolate Milk is rich in protein and calcium, while chocolate contains oxalic acid, the two will combine to form insoluble calcium oxalate, which greatly affects the absorption of calcium, and may even cause dry hair, diarrhea, slow growth and other phenomena. Milk is not suitable for drinking one hour before and after taking medicine because milk tends to form a covering film on the surface of the medicine, so that calcium, magnesium and other minerals in milk react chemically with the medicine and form non-water-soluble substances, thus affecting the release and absorption of the medicine.