Fit Body ScienceEvidence-based fitness analysis

In healthy Chinese people over 100 years old, the gut bacteria include fewer butyrate-producing species and more potential pathogens compared to younger adults.

See the scientific wording

In healthy Hainan Chinese centenarians aged 100+, gut microbial communities exhibit significantly reduced abundance of butyrate-producing bacteria including Faecalibacterium prausnitzii and Eubacterium hallii, and increased abundance of opportunistic pathogens including Escherichia coli, Desulfovibrio piger, and Methanobrevibacter smithii, with these microbial shifts associated with aging.

Supporting1 study

Correlational — new studies may shift this

Observational

One moderate-quality study links this claim to the outcome, but causation is not established.

What the research says

1 study reviewed

Supporting (1)

Moderate

Contradicting (0)

None

No contradicting studies found yet

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Why this might work

Less of the good bacteria that make butyrate weakens the gut lining, letting harmful bacteria and their toxins leak into the blood, which triggers constant low-level inflammation throughout the body.

Supported mechanismbased on 1 study

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting study

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