An interventional study of mixed meal test in Fasting, sponsored by ETH Zurich. Recruiting at 1 site in Switzerland. Open to participants aged 18 Years to 40 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-05-30.
Sponsored by ETH Zurich · Not applicable, Interventional, and Basic science
Fasting reduces the energy consumption of the human body. The extent of this adaptation varies significantly between different individuals. The aim of this research project is to investigate how this adaptation of the metabolism is regulated by the body. For this purpose, we will first measure how the so-called basal metabolic rate of the body reacts to a short-term fasting of 24 h in a preliminary study. Those subjects with a particularly pronounced and those subjects with an only slightly pronounced reaction of the basal metabolic rate will be invited to the main study.
Here, in random order (24 h fasting vs. 8 h fasting), the following is compared
The extent of this adaptation varies significantly between different individuals. The aim of this research project is to investigate how this adaptation of the metabolism is regulated by the body. For this purpose, we will first measure how the so-called basal metabolic rate of the body reacts to a short-term fasting of 24 h in a preliminary study. Those subjects with a particularly pronounced and those subjects with an only slightly pronounced reaction of the basal metabolic rate will be invited to the main study.
Fasting for 24 hours
Other: mixed meal test
Fasting for 12 hours
Other: mixed meal test
mixed meal test after fasting
change of energy expenditure (EE) determined by indirect calorimetry (kcal per 24h)
Difference of EE (determined by indirect calorimetry) between baseline and 60 minutes after ingestion of the liquid test meal. Both measurements will be performed after an overnight fasting period.
Time frame: 60 minutes after ingestion of test meal
Level of free thyroxine
The thyroid hormone (TH) system is an important regulator of EE. We hypothesize that levels of TH are higher in the "spendthrift" than in the "thrifty" group.
Time frame: after 24 hours and after 12 hours of fasting
Level of free triiodothyronine
The thyroid hormone (TH) system is an important regulator of EE. We hypothesize that levels of TH are higher in the "spendthrift" than in the "thrifty" group.
Time frame: after 24 hours and after 12 hours of fasting
Respiratory quotient (RQ)
We hypothesize that the participants in the "thrifty" group have a lower proportion of fatty acid metabolism and therefore a higher RQ.
Time frame: after 24 hours and after 12 hours of fasting
Plan to share: No
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