How common is lactose intolerance?

Lactose intolerance is quite common, affecting approximately 65-75% of the global population to some degree. Its prevalence varies significantly by ethnicity; it is more common in people of East Asian, West African, Arab, and Indigenous American descent, while those of Northern European descent tend to have a lower incidence. Symptoms can range from mild discomfort to severe gastrointestinal issues after consuming lactose-containing foods.