# Allyl Dimethyl Sulfonium: A Novel Urinary Biomarker of Allium Consumption

## TL;DR

A new urinary biomarker, allyl dimethyl sulfonium, was discovered to track Allium food consumption and varies among individuals due to genetic differences.

## Contribution

ADMS is identified as a novel human metabolite and potential biomarker for Allium intake.

## Key findings

- ADMS was consistently detected in all volunteers over 6 weeks.
- Urinary ADMS levels strongly responded to controlled garlic supplementation.
- Interindividual variability in ADMS levels mirrors other INMT products and is linked to genetic variation.

## Abstract

Allyl methyl sulfide (AMS) is an odorous and bioactive
major metabolite
produced following Allium food consumption and is
regarded as the culprit behind the “garlic breath”.
Indoleethylamine N-methyltransferase (INMT) can methylate
a variety of thioethers to their respective sulfonium ions in humans,
aiding in their urinary excretion. We hypothesize that AMS may serve
as a novel target for INMT and be metabolized to the allyl dimethyl
sulfonium (ADMS) ion, which would constitute a previously undescribed
pathway for metabolism of Allium food. ADMS was synthesized,
and analytical methods were developed to explore its existence and
characterize its levels in humans. ADMS was indeed consistently detected
in all volunteers over 6 weeks without dietary intervention and found
to strongly respond to controlled garlic supplementation. Striking
interindividual variability in urinary ADMS was observed and found
to mirror other products of INMT, which is attributable to genetic
variation. ADMS is a novel metabolite in humans, and its remarkably
variable production suggests variable response in body odors and health
effects of Allium food and can be used to assess Allium consumption in the general human population in future
epidemiological studies. More products of INMT that can serve as biomarkers
of sulfur-rich food intake await discovery.