Distinct plant species per week — the strongest dietary predictor of diversity.
The American Gut Project — the largest crowdsourced human study to date — found that people eating 30+ different plant species per week had significantly more diverse gut microbiomes than those eating 10 or fewer, regardless of whether they identified as vegan or omnivore.
What the researchers did
McDonald and colleagues sequenced stool samples and dietary questionnaires from 11,336 participants across the US, UK and Australia to identify dietary patterns that predict composition.
The key finding
was the single strongest dietary predictor of gut alpha diversity — beating vegan/omnivore status, , and . Higher-diversity guts had less antibiotic-resistance-gene load and healthier short-chain fatty acid profiles.
Why it matters
feed different microbes. A varied plant intake broadens your and polyphenol portfolio, which shapes immunity, mood and metabolic health via short-chain fatty acids.
Count plants, not portions. Herbs, spices, nuts, seeds, legumes and whole grains all count. Aim for 30 distinct species a week.
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- 7–9Nightly sleep for recovery, hormones and growth hormone release.
- 8,000Daily step count where all-cause mortality risk levels off — largely a NEAT effect.
- 3–5Creatine monohydrate dose — no loading needed.
- 3–6Pre-training caffeine dose that reliably improves strength and endurance output.
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