Appetite hormones and energy intake in obese men after consumption of fructose, glucose and whey protein beverages.
OBJECTIVE
To investigate appetite responses over 4 h to fructose beverages in obese men, relative to glucose and whey protein. Second, to investigate the effect of combining whey and fructose on postprandial appetite hormones.


METHODS
Randomized, double-blind crossover study of four beverages (1.1 MJ) containing 50 g of whey, fructose, glucose or 25 g whey+25 g fructose. Blood samples and appetite ratings were collected for 4 h then a buffet meal was offered.


METHODS
Twenty-eight obese men (age: 57.0+/-1.6 years, body mass index: 32.5+/-0.6 kg/m(2)).


METHODS
Plasma ghrelin (total), glucagon-like peptide-1 (GLP-1 7-36), cholecystokinin-8, glucose, insulin and appetite ratings were assessed at baseline and 30, 45, 60, 90, 120, 180, 240 min after beverages, followed by measurement of ad libitum energy intake.


RESULTS
Fructose produced lower glycaemia and insulinaemia compared to the glucose treatment (P<0.0001); whereas postprandial ghrelin, GLP-1 and cholecystokinin responses were similar after both treatments. Whey protein produced a prolonged (2-4 h) suppression of ghrelin (P=0.001) and elevation of GLP-1 (P=0.002) and cholecystokinin (P=0.003) that were reduced when combined with fructose, while glucose and insulin responses were similar. Energy intake after 4 h was independent of beverage type (glucose 4.7+/-0.2 MJ; fructose 4.9+/-0.3 MJ; whey 4.6+/-0.3 MJ; whey/fructose 4.8+/-0.3 MJ; P>0.05).


CONCLUSIONS
In obese men, fructose- and glucose-based beverages had similar effects on appetite and associated regulatory hormones, independent of the differing glycaemic and insulinaemic responses. The contrasting profile of plasma ghrelin, GLP-1 and cholecystokinin after whey protein consumption did not impact on ad libitum intake 4 h later and was attenuated when 50% of whey was replaced with fructose.
Bowen
J
J
Commonwealth Scientific and Industrial Research Organisation, Human Nutrition, Adelaide, Australia. jane.bowen@csiro.au
Noakes
M
M
Clifton
P M
PM
D001066:Appetite / Q000187:drug effects; D001628:Beverages; D001786:Blood Glucose / Q000378:metabolism; D002766:Cholecystokinin / Q000097:blood; D018592:Cross-Over Studies; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D004311:Double-Blind Method; D002149:Energy Intake / Q000187:drug effects*; D005632:Fructose / Q000494:pharmacology; D054439:Ghrelin / Q000097:blood; D052216:Glucagon-Like Peptide 1 / Q000097:blood; D005947:Glucose / Q000494:pharmacology; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D008875:Middle Aged; D008894:Milk Proteins / Q000494:pharmacology*; D009765:Obesity / Q000097:blood / Q000503:physiopathology*; D010446:Peptide Fragments / Q000097:blood; D036361:Peptide Hormones / Q000097:blood*; D000067816:Whey Proteins
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D054439:Ghrelin; D007328:Insulin; D008894:Milk Proteins; D010446:Peptide Fragments; D036361:Peptide Hormones; D000067816:Whey Proteins; C410885:cholecystokinin 8; D005632:Fructose; D052216:Glucagon-Like Peptide 1; D002766:Cholecystokinin; D005947:Glucose