You may have heard that red heads experience more pain. It is also common for different ethnic groups to show a variety of responses to pain. Now researchers at University of Pittsburgh School of Medicine in Pennsylvania have tested whether eye color affects pain tolerance.
The study involved 58 pregnant women who all gave birth at UPMC Magee Women's Hospital. The women were all Caucasian, 24 had dark colored eyes (brown or hazel) and 34 had light colored eyes (green or blue).
The researchers assessed antepartum and postpartum pain, mood, sleep and coping using standard surveys that rank these types of subjective characteristics.
What was found was that the dark-eyed women experienced more pain, more anxiety, increased sleep disturbances and were more likely to be depressed than their light-eyed counter parts.
Now it is important to note, the increase was not considered to be statistically significant. The researchers indicate that the results are only considered to show a trend.
The lead researcher Inna Belfer, MD, PhD stated, “Due to the small sample size, we can't get compelling evidence for our findings, but we do feel that our study has revealed patterns that warrant further studies.”
Belfer went on to say that the response to pain could also be genetic and that there is limited previous research available that has examined pain perception and eye color.
Gregory Terman, MD, PhD, president-elect of the American Pain Society and director of pain medicine research at the University of Washington in Seattle, also said that it is unknown as to why there would be a connection between pain response and eye color.
He too stated that it may be due to genetics. Terman said that further research could be interesting.
Commenters on the news reports on this study brought out a number of points that could be in play.