Research

Hormonal

Higher serum levels of indolepropionic acid (IPA), a gut microbiota metabolite derived from dietary tryptophan, are associated with a lower incidence of type 2 diabetes and reduced low-grade inflammation in high-risk individuals.

While you cannot directly supplement IPA effectively based on this study, the findings suggest that a diet high in fiber supports gut bacteria that produce IPA. This metabolic pathway is linked to lower inflammation and a reduced risk of type 2 diabetes. Prioritize fiber-rich whole foods to support this natural protective mechanism.

ModerateSupportsMEDIUM confidence
Higher IPA at 1-year study was inversely associated with the incidence of T2D (OR [CI]: 0.86 [0.73–0.99], P = 0.04)... Moreover, IPA correlated positively with dietary fiber intake... and negatively with hsCRP concentrations
Marjo Tuomainen et al. · Nutrition and Diabetes · 2018

Why this rating

Observational cohort study (Finnish Diabetes Prevention Study) with a relatively large sample size (n=403) and long follow-up (mean 7 years), but associations weakened after controlling for BMI and glucose.

Source

Associations of serum indolepropionic acid, a gut microbiota metabolite, with type 2 diabetes and low-grade inflammation in high-risk individuals

Marjo Tuomainen et al. · Nutrition and Diabetes · 2018

DOI 10.1038/s41387-018-0046-9

cohort · n=403Cited 236×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →