Metabolomics
Conditions
Brief summary
Fruit and vegetable (FV) intake has been reported as a modifiable risk factor of globally pervasive chronic diseases. Traditionally, the measurement of dietary intake has been conducted via self-report methods such as food diaries, food frequency questionnaires, and dietary recall. These methods are inherently subject to sources of error and biases. The objective measurement of diet-specific urinary biomarkers has been proposed as an alternate assessment method. A dose-dependent biomarker or biomarker panel for total FV intake has been investigated but not successfully established. In a recent publication as part of this PhD research, the researchers outlined a concise panel of 7 FVs that are predictive of total FV intake in a UK population. Recent studies have implemented an untargeted metabolomic approach to identify novel biomarkers of some of the 7 FVs identified in our prior research, but not with onion intake. The aim of this study is to detect, quantify and identify dose-dependent biomarker(s) of onion intake in a UK population using untargeted metabolomics. Phase 1 will be an acute randomised crossover intervention study, involving the consumption of a standardised portion of cooked onions (test) or couscous (control). Urine samples over the 24-hour period post-consumption will be collected. Phase 2 will be a dose-dependent crossover intervention study, where participants are supplied with supplementary onion portions (low, medium, high) to be consumed with their habitual evening meals. Within each supplementation period, participants will consume the same quantity of onions across the 4 days and collect a midstream first void urine samples on the fifth day. Trial order will be randomised, and a washout period of 3 days will be implemented between supplementation periods. 14 participants will be recruited for both phases of data collection. Urine samples will be analysed by high-performance liquid-chromatography with quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) to identify potential biomarkers.
Interventions
OTHEROnion Feeding
The intervention includes feeding individuals a 120g portion of onions (experimental condition).
OTHERCouscous Feeding
The intervention includes feeding individuals a 120g portion of couscous (control condition).
OTHEROnion Supplementation Period
Three 4-day supplementation periods separated by two 3-day washout periods. Supplementation periods will provide participants with a daily portion of onions to be consumed with their evening meals. The daily quantity of onion supplementation, low (40g), medium, (80g) and high (160g), will remain constant throughout each 4-day period, and the order will be individually randomised.
Sponsors
University of Nottingham
Manchester Metropolitan University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Healthy * Non-pregnant/lactating * BMI between 18.5 and 30 kg/m\^2 * Non-smokers.
Exclusion criteria
* Any diagnosed health condition (chronic or infectious diseases) * Consumption of medications/nutritional supplements * Any allergies/intolerances to onions/couscous.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Untargeted metabolomics for onion biomarker identification using LC-QTOF-MS. | 24-hours postprandial period following onion or couscous consumption. | Urine samples will be analysed to putatively identify biomarkers of onion intake by comparison with control samples using high-performance liquid chromatography coupled to a quadrupole time-of-flight mass spectrometer (LC-QTOF-MS). LC-QTOF-MS analysis allows the simultaneous high-resolution measurement of a broad range of metabolites, hence the untargeted nature of the analysis. Multivariate statistical analysis and Partial least squares Discriminant Analysis included in the mass spectrometry software will be used to analyse LC-QTOF-MS results to identify features that best discriminate between test and control conditions. |
| Dose-dependency and change in concentration of potential biomarkers identified in Primary Outcome 1 | First morning void urine samples following three periods of 4-day onion supplementation. | First morning void urine samples will be obtained after three separate 4-day periods of supplementing evening meals with 40g, 80g and 160g of onions. The validity of candidate biomarkers from the first phase of the study, Primary Outcome 1, shall be assessed by LC-QTOF-MS - quantifying urinary concentrations following the consumption of multiple doses of onions across a range of servings. |
Countries
United Kingdom
Outcome results
None listed