Redheads and pain tolerance – scientific facts and myths

Red hair is rare. While about 80 percent of people carry the possibility of having a ginger for a child, thanks to the recessiveness of the genes, only a fraction of people actually have a natural carrot top. According to the Fischer-Saller scale with eight different colors of hair, red is the rarest with only between one and two percent of the world population having it (dyed reds excluded).

The exceptional color initiated numerous superstitions and myths related to redheads. It is believed they are bleeding more than others, they need more pain killers for the same effect, they can’t stand dentists, are much more sensitive to the heat and can stand cold much better than a majority of world population.

From the genetical point of view, there is some logic behind these believes, some of them being many centuries old. Let’s examine them one by one.

Image credit: http://color-red.yolasite.com/red-hair-paintings.php

Article published in Anesthesiology (2005 Mar; 102(3): 509–514) revealed tests done on 30 volunteers with red and 30 volunteers with dark hair. All of them were healthy women between 18 and 40 years. All experiments were done in the first ten days of menstrual cycles of participants at the same time of the day (8 a.m.). Tests were done with TSA-II Neurosensory Analyzer for heat stimuli.

Until recently it was believed that lighter skin offers a certain advantage in colder climates (largest percent of red-haired people lives in Scotland and Ireland) because it emits less radiation and thus saves some body heat.

Although this still might be true, redheads don't stand more pain caused by coldness. They are actually more sensitive to all changes of temperature.

It was also proved they need substantial higher quantities of lidocaine to suppress the pain than women with dark hair. In other words, they have higher resistance to local analgetic as lidocaine. There are several theories why is so, but none of them is adequately tested. The main concern related to this proven fact is the risk of overdose. If one patient needs four shots of a pain-killer, he definitely risks more than one who needs only half of dose.

A similar study was done at Louisville University in Kentucky in 2005, what leads us to the next chapter.

An article from Scandinavian Journal of Pain made on a similar group (20 redheads and 20 dark heads) confirmed the results presented above. They also made another experiment. It was done by injections of capsaicin (active substance in hot paprika). The study showed redheads are less sensitive to burning sensation caused by capsaicin what confirms anecdotical evidence about gingers who can eat spicier food than most others.

Redheads have significantly more fears and even phobias related to the dentist. Several studies in recent years examined this problem from different angles and it seems that the main reason is not in the pain itself.

The problem lies in the resistance to most used anesthetics. At least twice as more shots are required for a typical redhead than for a regular customer and the effect of so well-known dumb-lips is much shorter. For this reason much higher percentage of gingers avoids regular visits and the result is worse dental health.

Well, the main conclusion is not exactly flattering for scientists and medicine in particular. We obviously have only a rough idea how anesthesia works. We can say with a relatively high level of certainty that MC1R protein has some role in the pain reception, but this role is not a simple one. What we can say for sure is that red-haired people feel pain differently than dark-haired ones.

Pharmacogenetics, a new medicine field studying the different effect of the same medicine on different people, is promising exactly that.

Like it or not, being a redhead or not, the color red has a very special meaning for humankind. Here is an article dealing with the meanings of red color:

http://hubpages.com/education/red-color-meaning

I bet you can learn at least something new from it. Red is influential and it makes an instant impression. Redheads are special too. They are no better or worse than any other group. They are just different and we all love difference, don't we?