The Importance of Diet in Shaping Gut Microbiome Diversity

Introduction

What you eat plays a crucial role in maintaining the health of your gut microbiome, potentially even surpassing the influence of genetics. However, the impact of diet on the gut microbiome may vary among individuals from different countries with diverse dietary habits. Researchers have explored the relationship between diet and gut microbiota in a study involving 21,561 participants from the United States, the United Kingdom, and Italy.

Key Findings

The study revealed that the quantity of healthy plant-based foods consumed, rather than the specific type of diet followed, had a more significant effect on gut microbes linked to heart health. By analyzing stool samples and dietary patterns, researchers identified distinct microbial signatures associated with vegan, vegetarian, and omnivore diets.

Vegan diets were found to promote beneficial gut bacteria, particularly those that produce short-chain fatty acids beneficial for heart health. On the other hand, individuals consuming red meat had higher levels of microbes linked to meat digestion and increased risks of colon cancer, inflammatory bowel disease, and cardiovascular diseases. Vegetarians exhibited a gut microbial profile that fell between that of vegans and omnivores.

Impact of Food Choices

While omnivores shared some gut bacteria with vegetarians and vegans, particularly when consuming similar amounts of fruits, vegetables, whole grains, and pulses, the study highlighted that individuals following mixed diets tended to consume fewer healthy plant-based foods, limiting the potential gut health benefits.

Furthermore, the study indicated that food consumption led to the acquisition of food-related microbes, with dairy products playing a significant role. For instance, Streptococcus thermophilus, commonly used in yogurt production, was a key species distinguishing vegan and vegetarian gut microbiomes. Dairy, fruits, and vegetables transferred a higher number of microorganisms to the gut microbiome of omnivores and vegetarians compared to vegans, suggesting that food sources and cultivation practices contribute to gut microbiome diversity.

Conclusion

In conclusion, the study findings underscore the impact of dietary patterns on gut microbial diversity, with plant-based diets promoting gut health. While omnivores, vegans, and vegetarians share some common gut microbes influenced by overall diet, the study emphasizes the importance of consuming a variety of healthy plant-based foods for optimal gut health.

References

1. Fackelmann G, Manghi P, Carlino N, et al. Gut microbiome signatures of vegan, vegetarian and omnivore diets and associated health outcomes across 21,561 individuals. Nat Microbiol. 2025; 10(1):41-52. doi: 10.1038/s41564-024-01870-z.
2. Wicaksono WA, Cernava T, Wassermann B, et al. The edible plant microbiome: evidence for the occurrence of fruit and vegetable bacteria in the human gut. Gut Microbes. 2023; 15(2):2258565. doi: 10.1080/19490976.2023.2258565.