Breath 13CO2 - evidence for a non-invasive biomarker to measure added refined sugar uptake.

Increased consumption of added sucrose and high-fructose corn syrup in the human diet has been associated with increasing incidence of obesity and metabolic disease. There are currently no reliable, objective biomarkers for added sugar intake that could be used in individuals or population settings. 13C is a stable isotope of carbon and measurement of blood 13C content has been proposed as a marker of added sugar consumption. This study aimed to determine if breath 13CO2 could represent an alternative, non-invasive biomarker to monitor added sugar intake. We undertook retrospective analyses of eight pre-clinical and human 13C-breath studies to define baseline breath 13CO2 characteristics. All samples were analysed using isotope ratio mass spectrometry and breath 13CO2 was expressed as the delta value, δ expressed as parts per thousand (‰). All data is expressed as mean ± standard error of the mean, with statistical significance considered at p<0.05. Breath δ13CO2 was significantly elevated in a cumulative manner in rats and mice that consumed a diet containing at least 15% sucrose. Mice fed an American rodent chow diet containing 50% sucrose and 15% corn starch had a significantly higher breath δ13CO2 compared to rodents consuming an Australian rodent chow diet. Furthermore, breath δ13CO2 was significantly increased in a dose dependent manner in humans that ingested a bolus dose of sucrose. These findings suggest application for baseline breath δ13CO2 as a non-invasive biomarker for added sugar consumption, with broad application for longitudinal assessment of population sugar intake and obesity management strategies.