title: Bomb calorimetry, the gold standard for assessment of intestinal absorption capacity: normative values in healthy ambulant adults.
abstract: BACKGROUND
  Intestinal absorption capacity is considered to be the best method for assessing overall digestive intestinal function. Earlier reference values for intestinal function in healthy Dutch adults were based on a study that was conducted in an inpatient metabolic unit setting in a relatively small series. The present study aimed to readdress and describe the intestinal absorption capacity of healthy adults, who were consuming their usual (Western European) food and beverage diet, in a standard ambulatory setting.
  
  
  METHODS
  Twenty-three healthy subjects (aged 22-60 years) were included in the analyses. Nutritional intake (energy and macronutrients) was determined with a 4-day nutritional diary. Subsequently, mean faecal losses of energy (by bomb calorimetry), fat, protein and carbohydrate were determined following a 3-day faecal collection. Finally, intestinal absorption capacity was calculated from the differences between intake and losses.
  
  
  RESULTS
  Mean (SD) daily faeces production was 141 (49) g (29% dry weight), containing 891 (276) kJ [10.7 (1.3) kJ g(-1) wet faeces; 22.6 (2.5) kJ g(-1) dry faeces], 5.2 (2.2) g fat, 10.0 (3.8) g protein and 29.7 (11.7) g carbohydrates. Mean (SD) intestinal absorption capacity of healthy subjects was 89.4% (3.8%) for energy, 92.5% (3.7%) for fat, 86.9% (6.4%) for protein and 87.3% (6.6%) for carbohydrates.
  
  
  CONCLUSIONS
  The present study provides normative values for both stool nutrient composition and intestinal energy and macronutrient absorption in healthy adults on a regular Dutch diet in an ambulatory setting. Intestinal energy absorption was found to be approximately 90%.
authors: Department of Nutrition and Dietetics, VU University Medical Centre, Amsterdam, The Netherlands.
authors: N J
authors: NJ
authors: Wierdsma
authors: J H C
authors: JH
authors: Peters
authors: M A E
authors: MA
authors: van Bokhorst-de van der Schueren
authors: C J J
authors: CJ
authors: Mulder
authors: I
authors: I
authors: Metgod
authors: A A
authors: AA
authors: van Bodegraven
mesh_terms: D000328:Adult; D002151:Calorimetry / Q000379:methods* / Q000592:standards*; D015930:Diet Records; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004041:Dietary Fats / Q000008:administration & dosage; D004044:Dietary Proteins / Q000008:administration & dosage; D002149:Energy Intake; D005243:Feces / Q000737:chemistry; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007408:Intestinal Absorption / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D015596:Nutrition Assessment; D012016:Reference Values; D055815:Young Adult
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins
keywords: absorption; bomb calorimetry; faecal energy loss; healthy subjects