Taking the argument a bit last news, we can say that (without resorting to Leonardo or those who throughout history have used the fractional sleep as a lifestyle choice) in all periods of history has been used daily rest as a cure-all for improve the quality of our waking hours.
There are indeed people who literally can not live if you were to remove that twenty minutes after lunch when you leave the rest / sleep. For some it is an indispensable necessity and they are sick if they can not do a nap after lunch, compromising the quality of work activities.
To someone else instead, like myself, is totally inappropriate to do an afternoon siesta, under penalty of having a strong sense of numbness (not to use a more polished) for the remainder of the day.
There is an explanation of "physiological" in all of this? Yes You have to take into account the metabolic aspects, namely digestion. People who already tend to be rather slow and laborious digestion is good and after lunch we do a walk in order to keep awake the digestive function. Those who are quite stressed out and living with the frenetic pace is very easy to have an active metabolism and a bit too fast, so you can devote to a little afternoon siesta (usually no more than 20 minutes) to allow the digestive organs to play more relaxed their work. And to those who
sleepy after eating? Recommend a good cure for liver herbal, to restore functionality. Your herbalist will certainly advise you of confidence for the best.