Research

Micronutrients & recovery

The presence of uncultured gut bacteria encoding the ismA gene (cholesterol dehydrogenase) metabolizes intestinal cholesterol into coprostanol, which is poorly absorbed, thereby significantly reducing both fecal and serum total cholesterol levels in humans.

This paper identifies a specific group of gut bacteria (encoding the ismA gene) that converts cholesterol into a form (coprostanol) that your body doesn't absorb, lowering your blood cholesterol. The effect is as strong as your genetic predisposition. While you cannot currently prescribe these specific uncultured bacteria, this highlights that your gut microbiome is a key lever for heart health. Future interventions may target these bacteria to lower cholesterol without drugs.

GoodSupportsHIGH confidence
Individuals harboring coprostanol-forming microbes have significantly lower fecal cholesterol levels and lower serum total cholesterol with effects comparable to those attributed to variations in lipid homeostasis genes.
Douglas J. Kenny et al. · Cell Host & Microbe · 2020

Why this rating

Strong mechanistic validation (enzyme characterization) and robust observational association in large human cohorts (HMP2, PRISM), though causal inference relies on correlation rather than randomized controlled trials of bacterial transplantation.

Source

Cholesterol Metabolism by Uncultured Human Gut Bacteria Influences Host Cholesterol Level

Douglas J. Kenny et al. · Cell Host & Microbe · 2020

cohort · n=3097Cited 305×
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