NEW YORK, June 3: A recent study led by Dr. Li Jiao of Baylor College of Medicine has revealed new insights into how dairy products influence the gut microbiome — the complex community of microbes residing in the digestive system.

The research shows that milk consumption is associated with an increase in several beneficial bacteria, enhancing gut biodiversity and potentially contributing to better digestive health. Conversely, cheese consumption appears to reduce certain gut microbes important for maintaining intestinal balance.

Milk is known for its nutrients such as calcium and vitamin D, but this study highlights its role in supporting a broader range of gut microbes, which indicates a more adaptable and resilient gut environment. Scientists observed that milk intake promotes bacteria like Faecalibacterium, which helps regulate inflammation and maintain gut balance, and Akkermansia, linked to healthy weight management and blood sugar control.

Some researchers suggest that milk’s carbohydrate content, particularly lactose, may be responsible for encouraging these beneficial microbes, though further research is ongoing.

Unlike milk, cheese — produced through fermentation and containing less lactose — was found to decrease levels of Bacteroides and Subdoligranulum, both of which play roles in colon health and metabolic function.

The study also noted a possible increase in Bifidobacterium, a probiotic bacteria, with certain dairy consumption patterns, drawing interest from nutrition experts looking for dietary ways to support digestion.

Despite its reputation as a probiotic food, yogurt did not show significant effects on gut microbiota in this study. Researchers attributed this to low yogurt consumption among participants, which limited the ability to analyze its impact on key bacteria such as Akkermansia and Faecalibacterium. Future research with higher yogurt intake levels is needed to better understand how fermented dairy compares to milk and cheese.

Experts note that daily dairy recommendations vary depending on age, lifestyle, and health. Individuals with lactose sensitivity or digestive issues should choose dairy products carefully. While the U.S. dietary guidelines suggest about three cups of dairy per day, many people consume less, opening opportunities for considering how milk or cheese might enhance gut microbial diversity.

The study involved only 34 mostly older male participants and relied on self-reported dietary data, which can introduce inaccuracies. Consequently, the findings may not generalize to younger populations, women, or those with different eating habits.

Dr. Jiao emphasized that “dairy consumption may influence host health by modulating the structure and composition of the colonic adherent gut microbiota.” Future studies aim to examine long-term effects and explore how different dairy products affect gut microbes across diverse populations.

Understanding the interplay between nutrients like calcium and protein and the gut microbiome may lead to more personalized dietary guidelines that focus on the type of dairy consumed, rather than quantity alone, to promote digestive health.