Rough Diamond: A Carbon Isotopic Biomarker of Added Sugar Intake

Intra-Individual Stable Isotope Variation Tracks Brazilian Contemporary Dietary and Nutritional Transition

INTRODUCTION

Contemporary dietary and nutritional transitions are commonplace, but difficult to study directly. In Brazil, and Latin America, this generalized process, leading to current obesity and malnutrition problems, started more than four decades ago. Although body weight and food availability are used to measure changes, not much information on food consumption and nutrition exist. Stable isotope analysis allows for the study of modern individual diets because it reflects the proportional contribution of different foods, general dietary patterns, and the effect of metabolism. Furthermore, when samples from tissues reflecting different time points are used, it allows for the assessment of individual transitions.

OBJECTIVES

To explore intra-person isotopic variation for the first time in the Southern Hemisphere for modern humans, and examine the nutritional transition reported for Brazil in the past four decades.

MATERIALS

Stable carbon and nitrogen isotope values from 68 14C-dated bone samples (vertebra, occipital, parietal, femur) from 17 individuals born in 1963, from three cemeteries.

RESULTS

Data reflect chronologically ordered high intra-individual δ15N variation tracking the dietary and nutrition transition over the last few decades, while no relationship between δ13C values and time was found. Vertebrae, reflecting diets from the mid 2000s, showed lower δ15N values than other bones reflecting the mid 1980s and early 1990s.

DISCUSSION

We show how different bones capture nutritional transitions over the lifespan of modern individuals. Nitrogen isotope values were lower in recent tissues as a consequence of the changes in the agri-food industry and worldwide consumption patterns that have intensified in Latin America in the last decades.

A Systematic Review of Metabolomic Biomarkers for the Intake of Sugar-Sweetened and Low-Calorie Sweetened Beverages

Intake of added sugars (AS) is challenging to assess compared with total dietary sugar because of the lack of reliable assessment methods. The reliance on self-reported dietary data in observational studies is often cited as biased, with evidence of AS intake in relation to health outcomes rated as low to moderate quality. Sugar-sweetened beverages (SSBs) are a major source of AS. A regular and high intake of SSBs is associated with an overall poor diet, weight gain, and cardiometabolic risks. An elevated intake of low-calorie sweetened beverages (LCSBs), often regarded as healthier alternatives to SSBs, is also increasingly associated with increased risk for metabolic dysfunction. In this review, we systematically collate evidence and provide perspectives on the use of metabolomics for the discovery of candidate biomarkers associated with the intake of SSBs and LCSBs. We searched the Medline, Embase, Scopus, and Web of Science databases until the end of December 2020. Seventeen articles fulfilled our inclusion criteria. We evaluated specificity and validity of the identified biomarkers following Guidelines for Biomarker of Food Intake Reviews (BFIRev). We report that the ¹³C:¹²C carbon isotope ratio (δ¹³C), particularly, the δ¹³C of alanine is the most robust, sensitive, and specific biomarker of SSBs intake. Acesulfame-K, saccharin, sucralose, cyclamate, and steviol glucuronide showed moderate validity for predicting the short-term intake of LCSBs. More evidence is required to evaluate the validity of other panels of metabolites associated with the intake of SSBs.