On the origin of the saying "to have blue blood" to refer to the nobles, there are various theories
For centuries the expression "to have blue blood" indicates people of noble origins.
But where does this saying that we all know and probably use sometimes come from?
There are various theories about it.
One of the most accredited refers to the complexion, which in the past, in the aristocrats, was generally markedly clearer than in those who belonged to the poorest strata of the population.
The reason lay in their different way of life.
In fact, the commoners carried out humble and often heavy jobs, in most cases in the open air, so the sun darkened their skin.
The nobles, on the other hand, stayed longer in their spacious and comfortable abodes and almost never exposed themselves to the sun's rays, so their complexion remained so clear that the bluish veins were immediately visible. more superficial.
According to another theory instead, “blue blood” it would derive from frequent bruises and bluish swellings caused by haemophilia.
This hereditary disease in the past was very common in the wealthy classes, also because it was favored by the habit of being romantically linked to relatives, even close ones.
It should also be added that, in fact, judging from the portraits that have come down to us, the nobles almost always had very fair skin.
This certainly affected the luck of the expression "to have blue blood" ( Photo from :focusjunior.it).