Geriatrics Essentials: Involuntary Weight Loss Normal age-related changes that can contribute to weight loss include the following: Decreased sensitivity to certain appetite-stimulating mediators (eg, orexins, ghrelin, neuropeptide Y) and increased sensitivity to certain inhibitory mediators (eg, cholecystokinin, serotonin, corticotropin - releasing factor) A decreased rate of gastric-emptying (prolonging satiety) Decreased sensitivities of taste and smell Loss of muscle mass (sarcopenia) In older people, multiple chronic disorders often contribute to weight loss.