Clinical trial NCT06898840: Establishing the Glycaemic Index of Fruit Drinks Using Different Measurement Methodologies
Official title: Study to Examine Glycaemic Responses to the Ingestion of Fruit Juices and Smoothies Using Different Measurement Methodologies.
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Glycaemic Index
Glycaemic Response Measurements
Keywords: Fruit Drinks
Glycaemic Index
Lead sponsor: University of Bath
Sponsor class: OTHER
First posted: 2025-03-27
Enrollment: 10
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: Randomised, controlled, replicate crossover trial
Primary purpose: BASIC_SCIENCE

Brief summary: Glycaemic responses to carbohydrates ingested as fruit sugars may vary depending on factors inherent to the fruit and the type of sugar. The aim of this project is to investigate the glycaemic responses to a range of commercially available fruit drinks and to establish the glycaemic index for each product relative to a glucose reference. Differences in recorded responses could also be influenced by the sample type (capillary blood vs interstitial fluid) and participant characteristics. Participants will ingest 8 test drinks including 5 different fruit drinks (OJ, AJ, S\&B, ENERGISE, BLUE), each matched for carbohydrate to the glucose reference (CONTROL) which will be sampled two times, an additional sample of one of the smoothies (S\&B) will also be replicated. Fingerstick capillary blood sampling alongside dual sited continuous glucose monitors (CGM) will measure glucose and lactate concentrations, subjective appetite sensations will also be recorded. The tests will follow best practice guidelines for glycaemic index testing. These data will provide insight into how differing formulations can alter the glycaemic responses to fruit drinks, and whether sampling technique can affect the interpretations of measurement.


Eligibility criteria: Inclusion Criteria:

* Age: 18-65 years
* Body mass index 18-30 kg/m2

Exclusion Criteria:

* diagnosis of any form of diabetes
* intolerances or allergies to any of the study procedures (e.g. fructose/inulin intolerance)
* Fructose malabsorption
* Inborn errors of fructose metabolism (e.g. fructokinase deficiency, aldolase B deficiency, fructose-1,6-bisphosphatase deficiency)
* pregnant or lactating
* any condition that could introduce bias to the study (e.g. diagnoses of lipid disorders, including cardiovascular disease, or therapies that alter lipid or glucose metabolism, such as statins or niacin).

Primary outcomes:
measure: Glycaemic indices for 5 test drinks measured using capillary blood samples
timeFrame: 120 minutes
Secondary outcomes:
measure: Glycaemic index of all conditions with capillary blood samples vs CGM
timeFrame: 120 minutes
Other outcomes:
measure: Comparisons between conditions in glucose concentration in capillary samples
timeFrame: 120 minutes
measure: Comparisons between conditions in glucose concentration in capillary samples
timeFrame: 120 minutes
measure: Comparisons between conditions in glucose concentration in capillary samples
timeFrame: 120 minutes
measure: Comparisons between conditions in glucose concentration in capillary samples
timeFrame: 120 minutes
measure: Comparisons between conditions in glucose concentration with CGM
timeFrame: 120 minutes
measure: Comparisons between conditions in glucose concentration with CGM
timeFrame: 120 minutes
measure: Comparisons between conditions in glucose concentration with CGM
timeFrame: 120 minutes
measure: Comparisons between conditions in glucose concentration with CGM
timeFrame: 120 minutes
measure: Comparisons between conditions in lactate concentration in capillary samples
timeFrame: 120 minutes
measure: Comparisons between conditions in lactate concentration in capillary samples
timeFrame: 120 minutes
measure: Comparisons between conditions in lactate concentration in capillary samples
timeFrame: 120 minutes
measure: Comparisons between conditions in lactate concentration in capillary samples
timeFrame: 120 minutes
measure: Comparisons between conditions of appetite ratings
timeFrame: 120 minutes
measure: Comparisons between individuals
timeFrame: 120 minutes
measure: Comparisons between individuals
timeFrame: 120 minutes
measure: Comparisons between individuals
timeFrame: 120 minutes
measure: Comparisons within individuals
timeFrame: 120 minutes
Locations:
city: Bath
country: United Kingdom
facility: Department for Health, University of Bath
Study officials:
References:
citation: Gonzalez JT. Are all sugars equal? Role of the food source in physiological responses to sugars with an emphasis on fruit and fruit juice. Eur J Nutr. 2024 Aug;63(5):1435-1451. doi: 10.1007/s00394-024-03365-3. Epub 2024 Mar 16.