Higher circulating concentrations of insulin , leptin , cholecystokinin and peptide-YY accord with reduced appetite and energy intakes in healthy older adults .
Interventions to reduce circulating levels of these hormones may be beneficial for combatting the anorexia of ageing
Ageing is associated with reduced appetite and energy intakes .
However , the mechanisms underlying this phenomenon are not fully understood .
This systematic review and meta- analysis quantified differences in circulating concentrations of appetite-related hormones between healthy older and younger adults .
Dose-Dependent Effects of Randomized Intraduodenal Whey-Protein Loads on Glucose, Gut Hormone, and Amino Acid Concentrations in Healthy Older and Younger Men
Protein-rich supplements are used widely for the prevention and management of malnutrition in older people . We have reported that healthy older , compared to younger , adults have less suppression of energy intake by whey-protein — effects on appetite-related hormones are unknown . The objective was to determine the effects of intraduodenally administered whey-protein on glucose , gut hormone , and amino acid concentrations , and their relation to subsequent ad libitum energy intake at a buffet meal , in healthy older and younger men .  Hydrolyzed whey-protein ( 30 kcal , 90 kcal , and 180 kcal ) and a saline control ( ~0 kcal ) were infused intraduodenally for 60 min in 10 younger ( 19–29 years , 73 ± 2 kg , 22 ± 1 kg/m2 ) and 10 older ( 68–81 years , 79 ± 2 kg , 26 ± 1 kg/m2 ) healthy men in a r and omized , double-blind fashion . Plasma insulin , glucagon , gastric inhibitory peptide ( GIP ) , glucagon-like peptide-1 ( GLP-1 ) , peptide tyrosine-tyrosine ( PYY ) , and amino acid concentrations , but not blood glucose , increased , while ghrelin decreased during the whey-protein infusions . Plasma GIP concentrations were greater in older than younger men . Energy intake correlated positively with plasma ghrelin and negatively with insulin , glucagon , GIP , GLP-1 , PYY , and amino acids concentrations ( p < 0.05 ) . In conclusion , intraduodenal whey-protein infusions result ed in increased GIP and comparable ghrelin , insulin , glucagon , GIP , GLP-1 , PYY , and amino acid responses in healthy older and younger men , which correlated to subsequent energy intake
Higher circulating concentrations of insulin , leptin , cholecystokinin and peptide-YY accord with reduced appetite and energy intakes in healthy older adults .
Interventions to reduce circulating levels of these hormones may be beneficial for combatting the anorexia of ageing
Ageing is associated with reduced appetite and energy intakes .
However , the mechanisms underlying this phenomenon are not fully understood .
This systematic review and meta- analysis quantified differences in circulating concentrations of appetite-related hormones between healthy older and younger adults .