Is there a hormone or group of hormones that regulates when we feel sleepy late at night, or in the morning? Or is sleepiness caused by some other non-hormonal mechanism? (e.g. pure psychological, or neuronal.)
Not enough serotonin production which later on turns into melatonin which is responsible for your sleep thus trowing of your circadian rhythm
Eating to much food can all your organs liver , pancreas, etc to work HARD to break down food do to lack of enzymes and this the result you feel sleepy. individuals also call this the “itis” which means inflamation in latin
Last but not least LACK OF SLEEP , can be from stress, Bright lights from tv, cellphones, other electronics etc
