Analysis of ancient dental plaque shows that Neanderthals from Spain and Belgium had different types of oral bacteria, and these differences were linked to how much meat they ate.
Mechanism
Synthesis from 1 study
The types of bacteria living in Neanderthals' mouths changed based on what they ate: meat eaters had different bacteria than plant eaters because each type of food feeds different kinds of microbes. This dietary selection created lasting differences in their oral bacteria, which we can still see in...
Most probable mechanism
When people eat mostly meat, bacteria that break down proteins and fats become more common in the mouth, while eating mostly plants favors bacteria that digest sugars and fibers. This change in food supply shifts which bacteria can survive and multiply, leading to completely different bacterial communities in the mouth depending on what was eaten.
Consumption of animal protein and fats provides nutrients that support the growth of bacteria specialized in breaking down amino acids and lipids.
Consumption of plant materials such as carbohydrates, polysaccharides, and fibers provides nutrients that favor bacteria capable of fermenting sugars and breaking down cellulose.
Nutrient-specific conditions in dental plaque create selective pressures that cause certain bacterial groups to dominate while others decline, resulting in distinct microbial community structures.
Long-term colonization by specific microbes, such as Methanobrevibacter oralis, leads to stable, adapted populations that persist across generations due to environmental consistency and vertical transmission.
Less supported by current evidence, but not ruled out
Ingesting plants with natural antimicrobial compounds, like salicylic acid or fungal antibiotics, may reduce certain oral bacteria and change the microbial balance, especially in individuals with infections.
Bioactive compounds from plants such as poplar bark and Penicillium fungus enter the oral cavity through ingestion.
These compounds inhibit the growth of specific bacteria or fungi in the mouth and gut, reducing microbial load.
Reduction in pathogenic or inflammatory microbes alters the overall composition of the oral microbiome.
Evidence from Studies
Supporting (1)
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Neanderthal behaviour, diet, and disease inferred from ancient DNA in dental calculus
Contradicting (0)
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Gold Standard Evidence Needed
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