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Data has shown that around 50 percent of Chinese suffer from bloating and indigestion due to consuming milk or dairy products, causing lactose intolerance, according to Nanfang Daily.

Though lactose intolerance may seem like a food allergy, it is in fact not. The inability of people to digest the principal sugar in milk is caused by a deficiency of the enzyme known as lactase.

Lactose intolerance is usually genetic and inherited, according to scientists. In most people the gene for lactase, the enzyme that digests lactose, is switched on at birth and off at the age of weaning. However, in most Europeans, the lactase gene remains active.