# Predictors of Fasting Endogenous Erythritol and Erythronate Concentrations in Humans: Cross-Sectional and Post-Bariatric Surgery Analyses

## TL;DR

This study explores how age and weight loss affect natural levels of erythritol and erythronate in human blood, finding age as a key factor.

## Contribution

The study identifies age and BMI as predictors of fasting erythritol and erythronate concentrations, with novel insights from bariatric surgery data.

## Key findings

- Age, not BMI or glucose, predicts fasting erythritol concentrations across populations.
- BMI and age both influence fasting erythronate concentrations.
- Post-surgery BMI changes predict erythritol changes, while time predicts erythronate changes.

## Abstract

The sugar alcohol erythritol occurs naturally in fruits and fermented foods, is used as a sweetener, and is also endogenously synthesized via the pentose-phosphate pathway and metabolized into erythronate. Untargeted metabolomic studies have associated elevated plasma erythritol and erythronate concentrations with metabolic disorders, while weight loss has been linked to decreased plasma erythritol concentrations. In this trial, two complementary analyses were performed to identify predictors of fasting erythritol and erythronate concentrations across different populations and to assess changes in these metabolites following bariatric surgery-induced weight loss. Fasting plasma samples from 30 lean adolescents, 50 lean adults, and 138 adults with obesity (including 15 who had undergone bariatric surgery) were analyzed to measure erythritol, erythronate, glucose, and insulin concentrations. Across all populations, age but not body mass index (BMI), glucose, or insulin, was a significant predictor of fasting erythritol concentrations. Fasting erythronate concentrations were associated with both age and BMI. Post-surgery, change in BMI but not fasting glucose or insulin was a predictor of changes in fasting erythritol concentrations, while time was the only predictor of changes in fasting erythronate concentrations. Although the metabolic processes regulating the endogenous erythritol and erythronate production remain unclear, our findings suggest that age-related physiological changes may influence fasting concentrations of both erythritol and erythronate.