An interventional study of Coca-Cola Zero Sugar and Still water in Healthy Adult Participants, sponsored by Czech University of Life Sciences Prague. Completed at 1 site in Czechia. Open to participants aged 18 Years to 60 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-07-23.
Sponsored by Czech University of Life Sciences Prague · Not applicable, Interventional, and Basic science
Consumption of beverages containing non-nutritive sweeteners has increased worldwide, but limited information is available regarding the short-term urinary excretion of acesulfame potassium (Ace-K) and the acute metabolic response following consumption of commercially available beverages. This study investigates the urinary pharmacokinetics of Ace-K and the acute urinary metabolomic response after consumption of 500 mL of Coca-Cola Zero Sugar in healthy adults. Participants complete two study arms under free-living conditions: Coca-Cola Zero Sugar and still water (control), separated by a one-month washout period. Urine samples are collected before beverage consumption and repeatedly over the subsequent 24 hours. Proton nuclear magnetic resonance (¹H NMR) spectroscopy is used to quantify Ace-K and other urinary metabolites. The study aims to determine the urinary appearance and elimination kinetics of Ace-K and to identify metabolic changes associated with Coca-Cola Zero Sugar consumption compared with water.
Non-nutritive sweeteners (NNS) are widely used as sugar substitutes in reduced-calorie foods and beverages. Among these, acesulfame potassium (Ace-K) is extensively incorporated into commercially available soft drinks because of its high sweetening potency, thermal stability, and minimal caloric contribution. Following oral ingestion, Ace-K is rapidly absorbed and excreted predominantly unchanged in urine, making it a promising biomarker of NNS consumption and dietary exposure. However, limited information is available regarding the urinary pharmacokinetics of Ace-K following consumption of commercially formulated beverages under free-living conditions.
Proton nuclear magnetic resonance (¹H NMR) spectroscopy enables simultaneous quantitative analysis of exogenous compounds and endogenous metabolites in complex biological samples. By applying the same analytical platform to both the intervention beverage and sequential urine samples, this study investigates the relationship between the ingested dose of Ace-K and its urinary excretion profile while simultaneously evaluating short-term metabolic responses following Coca-Cola Zero Sugar consumption.
This non-randomized, within-subject controlled study compares the urinary metabolomic response after consumption of Coca-Cola Zero Sugar with that observed following consumption of still water. The study aims to characterize the urinary appearance and elimination kinetics of Ace-K, quantify pharmacokinetic parameters including time to peak concentration and urinary elimination half-life, and explore acute changes in urinary metabolite profiles associated with Coca-Cola Zero Sugar consumption using quantitative ¹H NMR metabolomics.
Czech University of Life Sciences Prague is the lead sponsor of 3 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Participants consumed 500 mL of Coca-Cola Zero Sugar with breakfast. Spot urine samples were collected before beverage consumption and repeatedly over the subsequent 24-hour period for metabolomic and pharmacokinetic analyses using proton nuclear magnetic resonance (¹H NMR) spectroscopy.
Other: Coca-Cola Zero Sugar
Participants consumed 500 mL of still water with breakfast following a one-month washout period. Spot urine samples were collected before beverage consumption and repeatedly over the subsequent 24-hour period using the same sampling schedule as the Coca-Cola Zero Sugar arm.
Other: Still water
Participants consumed a single oral dose of 500 mL Coca-Cola Zero Sugar with breakfast. The intervention beverage was consumed within approximately 10-20 minutes. Spot urine samples were collected before consumption and repeatedly over the subsequent 24-hour period for metabolomic and pharmacokinetic analyses using proton nuclear magnetic resonance (¹H NMR) spectroscopy.
Also known as: Coke Zero
Participants consumed a single oral dose of 500 mL still water with breakfast under otherwise comparable conditions following a one-month washout period. Spot urine samples were collected before consumption and repeatedly over the subsequent 24-hour period using the same sampling schedule as the intervention arm.
Also known as: Control
Creatinine-normalized urinary acesulfame potassium (Ace-K) concentration (µM/mM creatinine)
Quantitative measurement of urinary acesulfame potassium (Ace-K) concentration following consumption of 500 mL Coca-Cola Zero Sugar and still water, determined by quantitative proton nuclear magnetic resonance (¹H NMR) spectroscopy. Concentrations will be normalized to urinary creatinine and reported at each scheduled urine collection time point.
Time frame: Baseline and each scheduled urine collection over 24 hours following beverage consumption.
Creatinine-normalized urinary metabolite concentrations (µM/mM creatinine)
Quantitative concentrations of individual endogenous and exogenous urinary metabolites measured by quantitative ¹H NMR spectroscopy. Each identified metabolite will be reported separately after normalization to urinary creatinine and compared between Coca-Cola Zero Sugar and still water interventions.
Time frame: Baseline and each scheduled urine collection over 24 hours following beverage consumption.
Area under the urinary acesulfame potassium concentration-time curve (AUC₀-₂₄)
Area under the creatinine-normalized urinary acesulfame potassium concentration-time curve calculated using the trapezoidal rule over the 24-hour sampling period.
Time frame: Up to 24 hours after beverage consumption
Concentrations of selected constituents in Coca-Cola Zero Sugar (µg/mL)
Quantitative concentrations of selected constituents in the intervention beverage, including acesulfame potassium, sodium cyclamate, aspartame, caffeine, citrate, glucose, glycerol, propylene glycol, phenylalanine, and other identified compounds, determined by quantitative proton nuclear magnetic resonance (¹H NMR) spectroscopy. Individual constituents will be reported separately in µg/mL and used to determine the administered dose of beverage components.
Time frame: Prior to participant consumption (baseline beverage characterization)
Plan to share: No — Individual participant data will not be made publicly available. De-identified data may be considered for sharing upon reasonable request to the study investigators, subject to institutional policies, ethical approval, and applicable data protection regulations.
No publications or documents are linked to this record.
This study is completed, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Czech University of Life Sciences Prague