This makes the kidneys less permeable to water, more water flows to the bladder. This increased loss of water upsets the balance of the electrolyte concentration and negatively affects the metabolic process. This can cause dehydration in chronic alcohol consumers.
The hormones insulin and cholecystokinin (CCK) are released from the GI tract during food absorption and act to suppress feeling of hunger. CCK is key in suppressing hunger because of its role in inhibiting neuropeptide Y. Glucagon and epinephrin levels rise during fasting and stimulate hunger.
A hormone produced by the pineal gland in darkness but not in bright light. Melatonin receptors in the brain react to this hormone and synchronize the body to the 24 hour day/night rhythm, thus informing the brain when it is day and when it is night.