Is it true that … we’re all a little bit intolerant to dairy?

Occasional sensitivity to lactose can occur as we get older, or through stress, but for most people it's only temporary

Most of us aren't inherently dairy intolerant, but we can go through periods where we become more sensitive to lactose in our diet, says Amanda Avery, an associate professor in nutrition and dietetics at the University of Nottingham.

She says that when people talk about being dairy intolerant", they're usually referring to lactose, the sugar found in milk and dairy products, such as milk, cheese and yoghurt. In most people, that sugar is broken down by an enzyme called lactase, which is found in our small intestine. It helps our bodies digest and absorb lactose without causing discomfort. We're born with plenty of lactase. But as our diets diversify, our lactase levels decline," says Avery. If there is minimal milk in the dairy diet then lactase levels may be zero, thus people from some cultural backgrounds and countries where dairy intake is negligible may be intolerant."