Microbial Taxa and Function in Lactase Non-Persisters

RESEARCHER: Danielle Lemay, UC Davis

TIMELINE: January 2022 – December 2023

BACKGROUND: Many Americans are genetically lactose intolerant (also known as “lactose non-persisters”). In a cross-sectional study of healthy adults in California (n=349), nearly 40% were shown to be lactase non-persisters. However, some of these lactase non-persisters are still able to consume more than 12g lactose per day. Preliminary data suggests potential adaptation of gut microbiome to dairy products in consumers who are genetically lactose intolerant.

OBJECTIVE: To understand how to help lactose intolerant people consume more milk so that they derive the nutritional benefits of dairy. Determine whether genetically lactose intolerant adults who consume lactose also produce more short chain fatty acids, especially acetate. Determine which microbes are the source of microbial lactase in genetically intolerant people.

INDUSTRY BENEFIT: Leverages large investments by USDA (> $4 million), uses banked samples from a USDA Nutritional Phenotyping Study (cross-sectional study of 396 Californians). The study aims to provide evidence for personalized dietary recommendations for dairy consumption. This would be an improvement over the current recommendation for lactose intolerant consumers to reduce/eliminate dairy intake, especially fluid milk. Currently, lactose is not considered a health benefit. But if it can be shown that increased lactose consumption is associated with increased beneficial metabolic compounds, this may create marketing opportunities and bring more consumers back to milk.