There's no fighting it: We're all destined to become gray ladies in time. Thanks to Tara Parker-Pope's blog, here's a bit more about what makes that so.
We know that hair turns gray as we age, but scientists are beginning to understand exactly how it happens. Our hair cells produce hydrogen peroxide, and over time, it builds up, blocking the synthesis of melanin (which provides the natural color to our hair). So when our hair turns gray, it's like a bleaching process from the inside out. That's only one part of the process, though. Researchers are using this discovery to examine whether stress can cause accelerated graying, which may sound like a vain pursuit — but that's not the case. By studying the stem cells involved in graying, scientists hope to discover treatments for melanoma. Think of that the next time a silver hair surfaces on your head.