Some persons do not digest milk well and may have a stomachache or diarrhoea after drinking it*. These people are called « lactose-intolerant » (don’t tolerate the lactose in milk) because they do not have sufficient lactase, the enzyme that is required to digest this milk sugar. They can however – without experiencing symptoms – eat ripened cheeses (which contain much less lactose), yoghurts or other fermented milks (in which lactose is broken down by the lactic bacteria).

* Most people however do tolerate milk in small quantities (up to 250 ml) or when it is mixed with other food (in mashes, for example).