"News for Redheads
Tue Oct 15, 1:11 PM ET
WASHINGTON (Reuters) - Redheads may actually
have another trait that makes them stand out -- sensitivity to pain, specialists reported on Tuesday.
People with natural red hair need about 20 percent more anesthesia than people with other hair colors, they told a
meeting of anesthesiologists. The unexpected finding not only suggests that redheads are more sensitive to pain, but offers
insights into how anesthesia works in people.
"Red hair is the first visible human trait, or phenotype, that is
linked to anesthetic requirement," Dr. Edwin Liem of the University of Louisville in Kentucky said in a statement.
"In a nutshell, redheads are likely to experience more pain from a given stimulus and therefore require more
anesthesia to alleviate that pain," he added.
Liem, who reported his findings to a meeting in Orlando, Florida of the
American Society of Anesthesiologists, said the finding is important news for specialists who monitor patients during
"The art and science of anesthesiology is choosing the right dose," he said. "There is very little
difference between the effective dose and the toxic dose of most anesthetics. Patients can awaken during surgery if they are
given insufficient anesthesia or suffer cardiac and pulmonary complications when they are given too much."
scientists do not fully understand how anesthesia works, but the findings offers clues, as people with red hair have a
certain genetic variant.
"Since red hair can be traced to particular mutations (variations) in the melanocortin 1
receptor, we now have the opportunity to evaluate central nervous system pathways that may influence or mediate anesthetic
requirement," Liem said.
"Investigating the role of melanocortin system in the central nervous system is thus likely
to help us understand fundamental questions such as which systems in the brain produce unconsciousness and which modulate
Liem's team studied white women aged 19 to 40 who were given the inhaled anesthetic desflurane.
Their physical responses were closely monitored, especially unconscious reflex arm or leg movement in response to painful
More anesthesia was needed to block movement in redheads than in participants with dark or blond hair,
What constantly amazes me is the huge increase in knowledge about the human body that we have obtained
in only the last few years. It's stuff like this that makes me want to be around for another 50 years!