The Study
Tree-based Analysis of Dietary Diversity Captures Associations between Fiber Intake and Gut Microbiota Composition in a Healthy U.S. Adult Cohort.
This study looked at what people ate and what bacteria were in their poop, and found that people who ate more fruit had more of a certain kind of bacteria. But it didn't change anyone's diet to see if that caused the change—so we don't know if the fruit made the bacteria grow, or if people with those bacteria just liked fruit more.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
Scientists looked at what people ate and what bacteria lived in their poop. They found that eating 30+ kinds of plants a week and more fiber from fruits (like apples and bananas, not berries) was linked to more diverse and healthier gut bugs.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 544 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes—this suggests eating a wide variety of plant foods, especially fruits, may help your gut bacteria thrive, which is linked to better digestion and overall health.
- 2People who ate more fiber from fruits had 21% stronger link to gut diversity (r=0.213).
- 3Those who ate more cooked grains had more Bifidobacterium.
- 4Lachnospira bacteria grew more when people ate fruit fiber.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
The Journal of nutrition
Year
2021
Authors
Mary E. Kable, Elizabeth L Chin, David H. Storms, D. Lemay, C. Stephensen
Related Content
Claims (6)
People who eat 30 or more different types of plants each week have higher gut microbiota diversity than those who eat fewer.
In healthy adults in the U.S., consuming more dietary fiber from fruits (not including berries) is linked to higher levels of the gut bacteria Lachnospira.
In healthy adults in the United States, people who eat a wider variety of foods based on evolutionary relationships between those foods have a greater diversity of microbes in their gut.
In healthy U.S. adults, the amount of dietary fiber consumed shows a stronger statistical relationship with the diversity of gut microbes than the amount of carbohydrates, proteins, or fats consumed.
In healthy U.S. adults, eating more total carbohydrates from cooked grains is linked to higher levels of Bifidobacterium bacteria in the gut.
A dietary analysis method that uses detailed food types and macronutrient amounts detects stronger links between what people eat and their gut bacteria than methods that only use nutrient totals or broad food groups.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.