The δ13C Value of Fingerstick Blood Is a Valid, Reliable, and Sensitive Biomarker of Sugar-Sweetened Beverage Intake in Children and Adolescents.

Background: Reliance on self-reported dietary intake methods is a commonly cited research limitation, and dietary misreporting is a particular problem in children and adolescents. Objective indicators of dietary intake, such as dietary biomarkers, are needed to overcome this research limitation. The added sugar (AS) biomarker δ13C, which measures the relative abundance of 13C to 12C, has demonstrated preliminary validity in adults. Objective: The purpose of this investigation was to determine the comparative validity, test-retest reliability, and sensitivity of the δ13C biomarker to detect AS and sugar-sweetened beverage (SSB) intake using fingerstick blood samples in children and adolescents. Methods: Children (aged 6-11 y, n = 126, 56% male, mean ± SD age: 9 ± 2 y) and adolescents (aged 12-18 y, n = 200, 44% male, mean ± SD age: 15 ± 2 y) completed 4 testing sessions within a 3-wk period. Participants' height, weight, demographic characteristics, and health history were determined at the first session; 24-h recalls were obtained at each visit and fingerstick blood samples were collected at visits 1 and 3. Samples were analyzed for δ13C value using natural abundance stable isotope mass spectrometry. δ13C value was compared with dietary outcomes in the full sample, and in child and adolescent subgroups. t Tests and correlational analyses were used to assess biomarker validity and reliability, whereas logistic regression and area under the receiver-operator characteristic curve (AUC) were used to evaluate sensitivity. Results: Reported mean ± SD AS consumption was 82.2 ± 35.8 g/d and 329 ± 143 kcal/d, and SSB consumption was 222 ± 243 mL/d and 98 ± 103 kcal/d. Mean δ13C value was -19.65 ± 0.69‰, and was lower in children than in adolescents (-19.80 ± 0.67‰ compared with -19.56 ± 0.67‰, P = 0.002). δ13C values were similar across sessions (visit 1: -19.66 ± 0.68‰; visit 3: -19.64 ± 0.68‰; r = 0.99, P < 0.001) and were associated (P < 0.001) with intake of total AS (grams, kilocalories: r = 0.29) and SSB (milliliters, kilocalories: r = 0.35). The biomarker was able to better discriminate between high and low SSB consumers than high and low AS consumers, as demonstrated by the AUC (0.75 and 0.62, respectively). Conclusions: The δ13C biomarker is a promising, minimally invasive, objective biomarker of SSB intake in children and adolescents. Further evaluation using controlled feeding designs is warranted. Registered at clinicaltrials.gov as NCT02455388.

Evaluation of the Relative Validity and Test-Retest Reliability of a 15-Item Beverage Intake Questionnaire in Children and Adolescents.

BACKGROUND: Added sugar intake, in the form of sugar-sweetened beverages (SSBs), may contribute to weight gain and obesity development in children and adolescents. A valid and reliable brief beverage intake assessment tool for children and adolescents could facilitate research in this area. OBJECTIVE: The purpose of this investigation was to evaluate the relative validity and test-retest reliability of a 15-item beverage intake questionnaire (BEVQ) for assessing usual beverage intake in children and adolescents. DESIGN: This cross-sectional investigation included four study visits within a 2- to 3-week time period. PARTICIPANTS/SETTING: Participants (333 enrolled; 98% completion rate) were children aged 6 to 11 years and adolescents aged 12 to18 years recruited from the New River Valley, VA, region from January 2014 to September 2015. Study visits included assessment of height/weight, health history, and four 24-hour dietary recalls (24HRs). The BEVQ was completed at two visits (BEVQ 1, BEVQ 2). MAIN OUTCOME MEASURES: To evaluate relative validity, BEVQ 1 was compared with habitual beverage intake determined by the averaged 24HR. To evaluate test-retest reliability, BEVQ 1 was compared with BEVQ 2. STATISTICAL ANALYSES PERFORMED: Analyses included descriptive statistics, independent sample t tests, χ2 tests, one-way analysis of variance, paired sample t tests, and correlational analyses. RESULTS: In the full sample, self-reported water and total SSB intake were not different between BEVQ 1 and 24HR (mean differences 0±1 fl oz and 0±1 fl oz, respectively; both P values >0.05). Reported intake across all beverage categories was significantly correlated between BEVQ 1 and BEVQ 2 (P<0.001). In children (n=126), reported intake of milk and energy (in kilocalories) for total beverages was not different (all P values >0.05) between BEVQ 1 and 24HR (mean differences: whole milk=3±4 kcal, reduced-fat milk=9±5 kcal, and fat-free milk=7±6 kcal, which is 7±15 total beverage kilocalories). In adolescents (n=200), water and SSB kilocalories were not different (both P values >0.05) between BEVQ 1 and 24HR (mean differences: -1±1 fl oz and 12±9 kcal, respectively). CONCLUSIONS: A 15-item BEVQ provides results that are similar relative to multiple 24HRs for determining habitual milk and total beverage intake in children, and water and SSB intake in adolescents. The 15-item BEVQ is a reliable indicator of habitual beverage intake in both children and adolescents. Future studies could explore whether adjustments to BEVQ beverage categories, portion size, and format could improve the tool's ability to measure beverage intake in young populations.