An interventional study of Fasting condition and Sugar condition in Fasting and Fed, sponsored by University of Lausanne. Completed at 1 site in Switzerland. Open to participants aged 18 Years to 60 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2018-01-04.
Sponsored by University of Lausanne · Not applicable, Interventional, and Basic science
This study aims at assessing whether breath acetone concentration is a good bio-marker of instantaneous energy balance in healthy subjects.
Each participant will be studied on three occasions, separated by 1-4 weeks. Each evaluation will consist in the same set of metabolic measurements, but will be performed fasting or during administration of a 70% fat or 70% carbohydrate liquid diet, according to a randomized order.
On each occasion, subjects will consume a standardized dinner the day before the experiment. They will remain fasted since 10 pm until the test day.
On the day of the experiments, one venous cannula will be inserted into a forearm vein for the collection of blood samples. An indirect calorimetry (measurement of respiratory gas exchanges using a ventilated canopy at rest, or a face mask during exercise) will be performed throughout the 6-hour test to measure energy expenditure and net substrate oxidation rate. Blood samples will be obtained every 60 min for the measurement of plasma glucose, insulin, free fatty acids, and beta-hydroxybutyrate concentrations. Breath samples will be also collected every 60 min (in 500 ml sampling bag) for the measurement of breath acetone concentration using a novel gas analyzer based on infrared laser spectroscopy.
Measurements will be done during 3 consecutive periods:
392 studies on the registry are indexed under Fasting; 63 are open to participants now.
This study's enrollment of 8 is below the median of 45 across 311 interventional studies indexed under Fasting.
Browse Fasting studies →University of Lausanne is the lead sponsor of 55 studies on the registry; 6 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Effects of cumulated negative energy balance (fasting over 480 min) on breath acetone changes
Other: Fasting condition
Effects of sugar consumption on breath acetone changes
Other: Sugar condition
Effects of fat consumption on breath acetone changes
Other: Fat condition
Subjects will fast over the whole experimental period (480 min)
After a 2-h fasting state, subjects will ingest every hour a drink containing 70% carbohydrate, 15% fat and 15% protein and providing 1.5 X hourly resting energy requirement.
After a 2-h fasting state, subjects will ingest every hour a drink containing 70% fat, 15% carbohydrate and 15% protein and providing 1.5 X hourly resting energy requirement.
Breath acetone
Changes in breath acetone concentrations in conditions of positive vs. negative energy balance.
Time frame: Every 60 min from 0 to 420 min
Plasma parameters
Relationship between breath acetone and plasma beta-hydroxybutyrate, glucose, free fatty acids and insulin concentrations
Time frame: Every 60 min from 0 to 420 min
Plan to share: No
No publications or documents are linked to this record.
Ran from Nov 2016 to primary completion in Jun 2017, 7 months.
Of 144 non-industry interventional studies with no phase under Fasting, half reached primary completion within 19 months of starting (the median), counting those still running; a quarter within 6 and three quarters within 40. This study's 7 months is below that.
Counting every sponsor, half of 149 studies reached it within 18 months; a quarter within 6 and three quarters within 40.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Dec 2017. You cannot join it, but the record below documents what was studied.
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University of Lausanne