A redheaded woman looks striking, unusual and makes you think of Ireland but unfortunately according to researchers, being a redhead may also mean experiencing more pain and needing more anesthesia during medical procedures such as dental work.
Anesthesiologists used to think that it was an urban legend that redheads required more anesthesia but recently researchers have tested the hypothesis and found evidence that supports this old wives tale.
In a 2009 study reported in the Journal of American Dental Association, 144 participants (67 natural red-heads and 77 dark-haired) filled out surveys rating their anxiety and fear of dental pain based on their previous dental care experiences. The redheaded patients were more than twice more likely to avoid seeking dental care than the dark-haired patients due to these concerns.
The reason for their increased sensitivity to pain appears to be related to a mutation of a gene that produces melanin. MC1R (melanocortin-1 receptor) is a receptor involved in the production of pheomelanin. This specific type of melanin is what gives a person red hair and fair skin. Some brunettes also have a mutation of their MC1R gene but it occurs less often. The MC1R gene belongs to a group of receptors that interpret pain in the brain so in turn affect the body’s perception of pain.
Recognizing that fear of dental work may be related to inadequate pain control, in 2005 Dr. Daniel Sessler decided to test whether redheads were resistant to the effects of the injected anesthetic lidocaine, a similar drug to novacaine used by dentists. His research team tested 30 redheaded and 30 dark haired women by injecting lidocaine into the top skin layers of their thighs and measured their responses to pain, heat and cold. While the dark haired and redheaded women responded similarly in their pain responses, the red headed women were significantly more sensitive to both cold and hot sensations leading the researchers to conclude that redheaded women were more resistant to the effects of the lidocaine.