Gray hair is the result of melanocyte depletion in melanin synthesis and is related to age and heredity. Although ageing can occur at any age from adolescence, it most often occurs after age 40.
Do gray hairs grow faster than other hair?
It has been shown, by studying the expression of genes of keratins and associated proteins, that they are upregulated to double their activity in the active growth of white-gray hair, compared to pigmented-black hair, which indicates o suggests that gray hair has a greater activity in the active growth of hair.
Another interesting fact is that people with thick hair tend to have earlier graying than those with fine hair.
What is true in the legends that have survived to this day about the people who turned gray in one night?
What must be commented is that, except in the case of “one night”, the rest have a scientific explanation.
In the case of Queen Marie Antoinette of France, who is said to have grayed the night before her execution, it should be clarified that, as most of her hair was fine and dark, they hid the thick ones who were gray. Those fine hairs, due to the emotional stress of his execution, entered the telogen phase and fell, so when he appeared for his execution, a white head of hair was seen.
Apart from the episode of Queen Maria Antonieta, it was also observed in Saint Thomas More when he was going to be executed for not accepting that King Henry VIII was declared head of the Church of England.
The graying of the body and pubic hair occurs after 50 years, the axillary later and the eyebrows and eyelashes can become gray, to do it in an average time between the pubic and the axillary. They are certainly signs of aging.
Reference: Trichology Book 3rd edition, by Dr. Camacho and Dr. Tosti.