Which demographic is at the highest risk for lactose intolerance?

Lactose intolerance is a condition characterized by the inability to digest lactose, a sugar found in milk and dairy products, due to a deficiency of lactase, the enzyme required for its digestion. The prevalence of lactose intolerance varies significantly across ethnic groups and geographic locations.

Southeast Asians are among the populations with the highest rates of lactose intolerance. Studies indicate that as many as 90-100% of individuals in some Southeast Asian countries have reduced lactase activity compared to populations of Northern European descent, where a higher prevalence of lactase persistence is observed. This difference is largely a result of genetic variations that affect lactase production after weaning.

In contrast, White northern Europeans tend to have much lower rates of lactose intolerance, often attributed to historical dairy farming practices and cultural adaptations to dairy consumption. Middle Easterners and South Americans also have varying rates of lactose intolerance but generally do not match the levels seen in Southeast Asian populations.

Understanding these demographic trends is crucial for dietary planning and interventions, especially in clinical settings where dietary recommendations may need to consider an individual's ethnic background and potential lactose intolerance. This awareness can help avoid gastrointestinal distress in individuals who cannot tolerate lactose, enabling better nutritional compliance and overall health.