The aim of the study is to investigate the effect of liquid versus semi-solid meals on the regulation of energy balance in healthy young adults.The main questions it aims to answer are: * Does a protein-rich liquid meal result in less satiety and therefore higher ad libitum energy intake at the next meal than an isocaloric oatmeal with the same macronutrient ratio? * Is the consumption of a protein-rich liquid meal as a beverage in addition to an ad libitum oatmeal less compensated within the meal and at the next meal and provides thus a higher ad libitum energy intake than an isovolumetric noncaloric soft drink in addition to an ad libitum oatmeal? Researchers will compare a protein-rich liquid meal to an isocaloric oatmeal with matched macronutrient composition to answer the first question. Researchers will compare a protein-rich liquid meal + oatmeal to a noncaloric softdrink (water with sucralose and flavoring) + oatmeal to answer the second question. Participants will: * spend 4 intervention days in a metabolic chamber (whole room indirect calorimeter) * consume pre-definied preloads for breakfast and ad libitum lunch meals on 4 intervention days
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
SINGLE
Enrollment
20
An isocaloric amount (500 kcal) of a commercially available liquid meal with a matched macronutrient composition is consumed. After 5 hours, lunch is eaten ad libitum.
An isocaloric amount (500 kcal) of a commercially available semi-solid oatmeal with a matched macronutrient composition is consumed. After 5 hours, lunch is eaten ad libitum.
A predefined amount of a caloric drink (= liquid meal) together with an ad libitum amount of a semi-solid meal is consumed. After 5 hours, lunch is eaten ad libitum.
A predefined amount of a non-caloric drink (= water, sucralose, flavor) together with an ad libitum amount of a semi-solid meal is consumed. After 5 hours, lunch is eaten ad libitum.
Kiel University, Institute of Human Nutrition
Kiel, Germany
ad libitum energy intake
measured during preload and lunch \[kcal\] following the preload in both arms
Time frame: for 9 hours after the consumption of the preloads
gastric emptying
gastric half-emptying time \[min\] determined with 13C-sodium acetate breath test, only assessed during arm "isocaloric preload"
Time frame: for 4 hours after the consumption of the isocaloric preloads
eating rate at lunch
assessed during ad libitum lunch \[g/min\] following the preload in both arms
Time frame: at 5 hours after consumption of the preload
number of chews per bite at lunch
assessed during ad libitum lunch \[number\] following the preload in both arms
Time frame: at 5 hours after consumption of the preload
serum ghrelin concentrations
area under the serum ghrelin concentration curve over 3 hours
Time frame: for 3 hours after consumption of the isocaloric preloads
serum peptide-YY (PYY) concentrations
area under the serum PYY concentration curve over 3 hours
Time frame: for 3 hours after consumption of the isocaloric preloads
serum Glucagon-like Peptide 1 (GLP-1) concentrations
area under the serum GLP-1 concentration curve over 3 hours
Time frame: for 3 hours after consumption of the isocaloric preloads
energy expenditure
Measured as kcal for 9.5 hours in a whole room indirect calorimeter (WRIC), including the consumption of the preload and the ad libitum lunch.
Time frame: measured for 9.5 hours
macronutrient oxidation
Measured as respiratory exchange ratio (RER) for 9.5 hours in a whole room indirect calorimeter (WRIC), including the consumption of the preload and the ad libitum lunch.
Time frame: measured for 9.5 hours
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.