Illustrative stock photograph by Clark Douglas on Unsplash; it does not depict study participants, their meals, gut microbes, or results.
A higher “gut-friendly” diet score was associated with lower overall and cardiovascular mortality among U.S. adults with cardiovascular–kidney–metabolic risk. The result supports familiar whole-food choices, but it does not prove that the diet—or the microbiome—caused the difference.
What changed
Researchers analyzed 13,286 adults in National Health and Nutrition Examination Survey data collected from 2007 through 2018. During a median follow-up of 80 months, 1,207 participants died, including 368 from cardiovascular causes. Each standard increase in the diet score was associated with an 11% lower risk of death from any cause and a 17% lower cardiovascular-death risk.
How strong is the evidence?
Large prospective observational analysis. The nationally representative dataset, mortality follow-up, and multiple sensitivity checks are strengths. The score performed about as well as established healthy-eating measures. The authors reported no competing interests.
What remains uncertain
This was not a randomized diet trial. Food intake came from short dietary recalls, and healthier eaters may differ in exercise, medical care, income, or other ways that statistical adjustment cannot fully remove. Most importantly, no stool samples or gut-microbe measurements were collected; the score was based on foods previously associated with microbiome health. It should not be treated as a microbiome test.
Why it matters
Higher scores favored foods such as fiber-rich whole grains, chickpeas, soy, broccoli, avocado, fermented dairy, coffee, and cranberries, while limiting processed meat and refined grains. That pattern is reasonable, but no single food guarantees protection. For related evidence, see how lifestyle patterns tracked with measured gut microbes and our pantry and kitchen page.
Sources
Original study in Scientific Reports, published November 7, 2026.
