March 16, 2016
In honor of St. Patrick’s Day, HCA Virginia Physicians is giving a nod to all the wonderful redheads in our population. Some famous redheads include Lucille Ball, Ed Sheeran, Robert Redford, Emma Stone, and Great Britain’s Prince Harry. Red hair has been immortalized in Disney characters such as Merida from Brave, Anna from Frozen, and Ariel from The Little Mermaid, all strong-willed and independent heroines. Red hair is the rarest of the natural hair colors in humans, and was once considered a developmental advantage to those in far-north climates with scarce sunlight.
The British Isles are home to the greatest concentration of the world’s redheads. Scotland currently has the most, with 13% of the population having red hair and 40% carrying the recessive gene. Ireland has the second highest percentage at 10%, but a larger swath of the population carries the gene, at 46%. There are indigenous redheads in most areas of the world, but higher concentrations radiate from the areas around the Mediterranean Sea. Populations of redheads in the Americas, Oceania, and South Africa are largely attributed to emigration.
Per the National Institutes of Health, the MC1R gene provides instructions for making a protein called the melanocortin 1 receptor. This receptor plays an important role in normal pigmentation. The receptor is primarily located on the surface of melanocytes, which are specialized cells that produce melanin, the pigment giving skin, hair, and eyes their color.
The relative amounts of two types of melanin help determine the color of a person’s hair and skin. People who produce mostly eumelanin tend to have brown or black hair and dark skin that tans easily. Eumelanin also protects skin from damage caused by ultraviolet (UV) radiation in sunlight. People who produce mostly pheomelanin tend to have red (or blonde) hair, freckles, and light-colored skin that can burn easily.
What are the top health risks for redheads?
- Melanoma: Red hair and fair skin is a disastrous combination when it comes to the risk factors for melanoma, the most serious form of skin cancer. Because redheads lack significant amounts of eumelanin, their skin is exposed to more UV radiation, causing more damage from the sun’s harmful rays. Research conducted at Beth Israel Deaconess Medical Center and Boston University School of Medicine note that the red hair-causing mutation of MC1R also may be linked to the absence of a different gene, PTEN, which usually exists in tandem with MC1R and suppresses tumor growth.
- Skin Cancer: Not only are redheads at risk for Melanoma, specifically, but they are also at increased risk for general skin cancers, because of the ease of which damage occurs to their skin with overexposure. Duke University researchers compared melanin reactions to UV light exposure in people with all hair colors, and it took far less energy to create the cancer-causing free radicals in people with red hair.
- Parkinson’s Disease: According to a Harvard study, redheads have a nearly 50% higher risk for developing Parkinson’s, a neurological disorder which causes increasing difficulties with balance and coordination. While researchers aren’t entirely sure why this disease is connected to redheads, there is evidence that it is related to a mutation in a related gene that is known to deliver a higher risk for Parkinson’s.
- Pain Sensitivity: According to an article in the journal Anesthesiology, Cleveland Clinic anesthesiologist Daniel Sessler, MD, notes that redheads are more susceptible to physical pain than their darker-hued counterparts. They can require up to 20% more anesthesia in certain applications because they have been found to be more resistant to pain medications like local anesthetic Novocaine. The culprit of this pain receptor sensitivity is thought to be the same one that elevates risk for Parkinson’s.
The health news for redheads isn’t all bad, though. Because their fair skin soaks up greater amounts of Vitamin D, a key component of bone health, they are at lower risk for osteoporosis. Some scientists also believe that the genetics behind red hair are immune-boosting, preventing some cancers and autoimmune disorders.
Perhaps the most refreshing news for redheads is that despite the rumor mill, they are not joining the dinosaurs and going extinct. Though unique, with only 4% of the global population carrying the recessive MC1R gene, it still represents a significant amount of the total number of people on the planet. As redheads reproduce with non-redheads, the trait may become rarer than it is today, but isn’t in any kind of danger of vanishing entirely.
For further questions about preventive medicine, general health and wellness, or to schedule an appointment for a consultation, contact Karen Galichon, MD, of Primary Health Group – Henrico, at 804-282-2580.