9 Nov 2009 --- Prevalence of lactose intolerance may be far lower than previously estimated, according to a study in the latest issue of Nutrition Today. The study, which uses data from a national sample of three ethnic groups, reveals that the overall prevalence rate of self-reported lactose intolerance is 12 percent – with 7.72 percent of European Americans, 10.05 percent of Hispanic Americans and 19.5 percent of African Americans who consider themselves lactose intolerant.

These new findings indicate that previous estimates of lactose intolerance incidence – based on the incidence of lactose maldigestion – may be overestimated by wide margins. Previous studies have found lactose maldigestion, or low lactase activity in the gut, to occur in approximately 15 percent of European Americans, 50 percent of Mexican Americans and 80 percent of African Americans. The new study shows that lactose intolerance, based on self-reported data, may actually occur far less frequently than presumed.

"There's so much confusion surrounding lactose intolerance," said Theresa Nicklas, DrPH, of the USDA/ARS Children's Nutrition Research Center at Baylor College of Medicine and lead study author. "By getting a better handle on the true number of people who deal with this condition every day, the nutrition community can be better equipped to educate and provide dietary guidance for Americans, including strategies to help meet dairy food recommendations for those who self-report lactose intolerance."

Since increasing daily consumption of dairy can be an effective strategy for ensuring adequate intake of shortfall nutrients (such as calcium, magnesium and potassium), those who do experience symptoms of lactose intolerance should know there are several practical solutions that can allow for consumption of milk and milk products. In fact, according to a recent study in the Journal of Sensory Studies, adults who identified themselves as lactose intolerant reported a higher liking of lactose-free cow's milk compared to non-dairy, soy-based substitute beverage.

"Those with lactose intolerance are often relieved to know they can still enjoy the great taste and health benefits of dairy if they follow certain strategies," said Orsolya Palacios, PhD, RD, and lead author of the study. "The symptoms of lactose intolerance vary greatly for each individual, and there are options in the dairy case that allow almost everyone to take advantage of the health benefits provided by the recommended three daily servings of dairy foods."

Several health authorities have addressed ways that those with lactose intolerance can benefit from dairy's unique nutrient package of nine essential nutrients including calcium, potassium, magnesium and vitamin A, identified as "nutrients of concern" by the current Dietary Guidelines for Americans. The Dietary Guidelines encourages people with lactose intolerance to try lower-lactose dairy food options to ensure they get the essential nutrients found in dairy. In a supplement to the October issue of the Journal of the National Medical Association (JNMA), the National Medical Association states that dairy milk alone provides a key package of essential nutrients, and that African Americans should use dietary strategies to increase the amount of dairy foods they consume. And in a 2006 report, the American Academy of Pediatrics (AAP) recommends children with lactose intolerance still consume dairy foods to help meet calcium, vitamin D, protein and other nutrient needs essential for bone health and overall growth. The report cautions that lactose intolerance should not require avoidance of dairy foods.