(OR37-02-24) Longitudinal Associations of Sugar-Sweetened Beverage Intake With Serum Carbon Isotope Ratio (CIR) in Youth: Findings From Two Independent Pediatric Cohort Studies

Objectives: The carbon isotope ratio (CIR) is a candidate biomarker for sugar-sweetened beverage (SSB) intake in the US; however, most research on CIR is in adults, and studies specific to pediatric populations, who tend to be higher SSB consumers, are lacking. Our objective was to examine longitudinal associations of SSB intake across childhood and adolescence with the serum CIR. We also explored associations for other food group intakes that may influence serum CIR.

Methods: Data were from subsets of participants from two longitudinal, observational cohort studies based in Colorado: the Exploring Perinatal Outcomes among CHildren Study (EPOCH) (n=150 children who completed visits at median 10 y and/or 16 y) and the Healthy Start Study (n=166 children who completed visits at median 5 y and/or 9 y). We measured serum CIR using blood collected at either or both visits using isotope ratio mass spectrometry (~80% of included children had samples at both visits). Dietary intake was assessed concurrently by food frequency questionnaire (EPOCH) or 24-hour recalls (Healthy Start). Associations of food group intakes (log₂-transformed and standardized) across visits with serum CIR were evaluated in linear mixed models adjusted for age, sex, and total energy intake for each cohort separately.

Results: The characteristics of participants were as follows: EPOCH: 44% male, 52% white, 41% Hispanic, 4% black, 3% other; Healthy Start: 51% males; 54% white, 28% Hispanic, 11% black, 8% other. In both cohorts, higher SSB intake was associated with higher serum CIR (Standardized β [95% CI]: 0.15 [0.09, 0.21] in EPOCH; 0.14 [0.07, 0.21] in Healthy Start). Other dietary intakes associated with serum CIR in both cohorts were: meat intake [β [95% CI]: 0.13 (0.08, 0.18] in EPOCH; 0.08 [0.01, 0.16] in Healthy Start) and whole fruit/fruit juice intake (-0.09 [-0.15, -0.04] in EPOCH; -0.09 [-0.16, -0.02] in Healthy Start).

Conclusions: These findings provide support for serum CIR as a potential biomarker of SSB consumption in youth. We also revealed associations of other dietary intakes, including meat and fruit intake, with serum CIR. Thus, additional efforts to evaluate and improve the specificity of CIR as a dietary biomarker are warranted. Future studies may also consider evaluating serum CIR as a biomarker of overall diet pattern.

Funding Sources: NIH (NIDDK, OD)