Developing Biomarkers of Dietary Intake: Dose Dependent Measurement of Sugar Intake

This study aims to find better ways to measure what people eat by looking at how different diets affect certain markers in your body. Researchers want to see if stable isotopes (a type of atom that can be tracked) can help identify how much sugar you consume. You would be a healthy volunteer between 18 and 65 years old. The study involves following specific diets, including one with no soda, one with 20% of carbohydrates from soda, and one with 50% of carbohydrates from soda. Researchers will measure changes in carbon stable isotope ratios in your blood and hair to see if these markers can accurately reflect your sugar intake. The study status is currently unclear.

Study design: This is an interventional study with a planned enrollment of 60 healthy volunteers. Participants will be assigned to different diets to see their effects.
What's involved: You would stay in an inpatient unit for 13 weeks, eating diets prepared by the NIH kitchen. You will have blood and urine tests at various times throughout the study.
Compensation: Not stated in the trial record.
Follow-up: Blood carbon stable isotope ratios will be measured up to 12 weeks, and hair carbon stable isotope ratios will be measured at 12 weeks.

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Developing Biomarkers of Dietary Intake: Dose Dependent Measurement of Sugar Intake

Recruiting

PHASE1Ages 18–65InterventionalBasic science

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

~60 participants

Updated 2026-09-14 on ClinicalTrials.gov

What's tested:Diet with no sodaDiet with 50% of carb intake from sodaDiet with 20% of carb intake from soda

At a glance

Recruiting sites

1 of 1 listed site is recruiting right now

RecruitingSuspended, closed, or not yet open

What they're measuring

Change in the blood carbon stable isotope ratio (13C/12C) from baseline to 12 weeks.

Measured over Baseline, Week 8, Week 10, Week 12

+1 more outcome measured

Conditions

Diet Therapy

Healthy Volunteers

NCT04799301

Where you'd take part

This study runs at 1 site. They're the same protocol — you choose where, and that choice sets who your contact draft is addressed to.

NIDDK, Phoenix
Phoenix, Arizonastudy coordinator listed
Recruiting

Sites open and close at different times, so the status above is per site — it can differ from the study's overall status.

Study leadership

Susanne M Votruba, Ph.D. · PRINCIPAL_INVESTIGATOR · National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Who to contact

Susanne M Votruba, Ph.D.

[email protected]

(602) 200-5336

Email the study team

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Eligibility criteria

Inclusion

Body mass index less than or equal to 35 kg/m\^2 to minimize the impact of body size on isotope measurements.

Women and men between the ages of 18-65 years will be recruited for this study

Healthy, as determined by medical history, physical examination, and laboratory tests.

Exclusion

Fasting plasma glucose greater than or equal to 126 mg/dL

Alopecia totalis or inability to grow hair (at least one inch of hair required to obtain sample)

Use of medication affecting metabolism and appetite in the last three months

Medically- or self-imposed dietary restrictions that would limit a participant s ability/willingness to consume the diet to which they are randomized

Current pregnancy, pregnancy within the past 6 months or currently lactating

History or clinical manifestations of acute or chronic disorders or conditions that may affect appetite or EE, (such as, but not limited to type 1 or type 2 diabetes, Cushing s disease, thyroid disorders, coccidiomycoses)

Gastrointestinal disease, including inflammatory bowel diseases (e.g. Chron s disease and ulcerative colitis), malabsorption syndromes (e.g. celiac disease), gastric ulcer (active) which may alter metabolism or absorption of study food

Current, unstable medical conditions such as hepatitis, renal insufficiency, cancer requiring treatment in the last 5 years (except for nonmelanoma skin cancers or cancers that have clearly been cured), or central nervous system disorders etc. as assessed by history and physical exam

Diagnosis of binge eating disorder, anorexia-nervosa, or bulimia-nervosa

Evidence of alcohol abuse as defined by greater than or equal to 8-point score on the Alcohol consumption screening AUDIT questionnaire in adults

Current use of tobacco products that exceed Low Dependence on the Fagerstrom Test for Nicotine Dependence Tool (score greater than 2)

Current use of drugs such as amphetamines, cocaine, or heroin

Any condition not specifically mentioned above that, in the opinion of the investigator, may interfere with the study or prove unsafe for participation.

Weight change of plus or minus 5% in the last 3 months, per self report.

Non-English speaking

Inability of participant to understand and the unwillingness to sign a written informed consent document.

What this trial measures

Change in the blood carbon stable isotope ratio (13C/12C) from baseline to 12 weeks.Baseline, Week 8, Week 10, Week 12
We will test biomarker diet relationships at the week 8, 10 and 12 sampling time points, using linear mixed effects models to evaluate single CIR biomarkers of SSB in plasma. Specifically, we will also test the time x group interaction by including it as a fixed effect in the mixed model analysis to evaluate the differences in the rate of CIR change over time across groups. Baseline CIR will be included as covariate in the mixed model analysis.
Change in the hair carbon stable isotope ratio (13C/12C) from baseline to 12 weeks.Baseline, Week 12
We will test biomarker diet relationships at baseline and 12 weeks to determine differences in values over time and dose.

Trialytics