10 Intriguing Scientific Facts About Redheads

Emma Stone. Lindsey Lohan. Julianne Moore. Nicole Kidman. Rihanna. Many famous celebs are ginger — gorgeously so. And many of us have flirted with being knockout redheads. But there are crazy facts about being born with this hair color that you probably DON'T know.

Think we're kidding? Check out these science-based facts about redheads.

1. Red's super rare. Only 2 percent of the world's population is thought to have red tresses. Scotland boasts the most redheads, with Ireland coming in a close second.

2. If you're ginger, you're having more sex. So says a German sex researcher who surveyed some 6,000 women. The results? Redheads had more partners AND more sex than women with any other hair color.

3. Red hair is associated with a higher risk of skin cancer. According to one study in the International Journal of Cancer, redheads are TWICE as likely to be diagnosed with melanoma than other peeps.

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4. Redheads are more likely to get Parkinson's. A 16-year-long study of over 130,000 people found that those with lighter hair colors had higher odds of being diagnosed with Parkinson's disease. Redheads in particular were twice as likely to have the degenerative nervous system disorder than those with black hair.

5. If you have a mane like Ariel's, you soak up more vitamin D. The pale, milky skin that usually accompanies red hair has at least one great upside: It absorbs more vitamin D, which is awesome for bone health, preventing osteoporosis, and boosting your immune system.

6. If you have red hair, you're probably left-handed. The reason? Both are recessive genes.

7. Redheads have a higher threshold to pain. Great to know when you're going into labor! One study found that gingers can withstand up to 25 percent more pain than non-redheads. It's a gene mutation thing.

8. Redheads are also harder to put under. Here's something else really good to know before you get an epidural during labor. (Although hopefully your anesthesiologist is clued in already.) Because of that same mutated gene that affects pain sensation, redheads require more anesthesia than the rest of the population.

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9. And probably have dental phobia. So, with all that resistance to anesthesia, it's probably not THAT surprising that redheads tend to have anxiety about going to the dentist. And are twice as likely to skip visits because of it.

10. Redheaded women are prone to endometriosis — or protected from it. This painful gynecological condition can cause heavy bleeding and cramping. Turns out, fertile redheaded women are more likely to have it, yet infertile redheaded women are less likely than other women.

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