This page is under construction

This page is under construction

Yogurt has been around for thousands of years. The action of certain bacteria change the lactose (a sugar) in the milk into a form that adults can easily digest. 

At some point, some people in Northern and Central Europe evolved to be able to digest the lactose in milk directly as adults. Everyone else loses the ability to digest lactose as they stop producing the enzyme lactase by age 5. This is called lactose intolerance - which can make them ill with bloating, diarrhoea and abdominal cramps. 

Lactase breaks lactose down into glucose and galactose, which can then be absorbed into the bloodstream and used for energy.

It's a great example of evolution as being able to digest milk as an adult provides an additional food source. Most Europeans are lactose tolerant as cows have been farmed for their milk for generations. By contrast, the most Chinese and Africans are lactose intolerant as dairy products have only recent been available. 75% of the world's population is lactose intolerant.

Please see the American Journal of Clinical Nutrition - The acceptability of milk and milk products in populations with a high prevalence of lactose intolerance