Why does drinking milk cause diarrhea?

Milk is a food rich in nutrients, but some people may have diarrhea after drinking milk. As for why diarrhea occurs after drinking milk, it cannot be ruled out that it is caused by milk allergy. Improper milk drinking habits can also cause diarrhea, such as drinking milk on an empty stomach. Eating it with chocolate can also cause diarrhea.

1. Drink milk on an empty stomach

Gastrointestinal motility is faster when the stomach is empty, and milk stays in the gastrointestinal tract for a short time and cannot fully come into contact with digestive enzymes. Its nutrients are "hastily" discharged into the large intestine before they have time to be digested, and cannot be fully absorbed and utilized.

2. Cook at high temperature for a long time

Milk is a heat-sensitive substance. When the temperature reaches 60℃~62℃, the protein particles in the milk will dehydrate and turn into a gel state, followed by precipitation. At the same time, the less stable acidic calcium phosphate in the milk will also turn into neutral calcium phosphate to form a precipitate.

If the heating temperature reaches about 100°C, the lactose in the milk will begin to caramelize and turn brown, and gradually decompose to produce lactic acid and a small amount of formaldehyde. If milk is cooked at high temperature for a long time, a lot of vitamins will be lost. Therefore, when cooking milk, just heat it until it just boils and then remove from the heat. It should not be cooked for a long time.

3. Mix with acid

After milk enters the gastrointestinal tract, the pepsin and trypsin in the gastric juice first combine with the protein in the milk, and then enters the small intestine. If you eat acidic drinks or fruits at this time, the protein in the milk, fruit acid and vitamin C will coagulate into lumps, which will not only affect digestion and absorption, but also cause symptoms such as diarrhea, abdominal pain, and bloating.

4. Add sugar and cook together

The lysine in milk and sugar will produce a chemical reaction called Maillard reaction under high temperature, generating a toxic substance - fructosyllysine, which is harmful to human health and even more harmful to children.

If you want to drink sweet milk, you should add sugar after the milk cools down a little after boiling. Similarly, milk should not be cooked with chocolate because chocolate is rich in oxalic acid. If they are cooked and eaten together, the calcium in the milk and oxalic acid will combine to form calcium oxalate, which is not easily absorbed and can also cause symptoms such as diarrhea.

5. Improper storage

When the temperature of iced milk is below zero degrees Celsius, the fat and protein in it separate, the casein coagulates into powder, the taste will be significantly weakened, and the nutrients will not be easily absorbed. If people often drink iced milk, it is also easy to cause the recurrence of gastrointestinal diseases such as ulcers, cholecystitis, enteritis, etc.