Do you ever feel a little bit overwhelmed by the sheer number of skin care ingredients you're expected to know about? Acids alone constitute a vast category of products, ranging from ultra-gentle skin-soothers like hyaluronic acid to more stringent, acne-eradicating varieties like salicylic acid — and they raise so many questions. Just how powerful are they? Are they going to freak your skin out? What the heck do they actually do to your skin? They can be kind of a scary — especially when used in conjunction with words like "resurfacing" or "peel."

Juggling a hectic, jet-setting career while maintaining a flawless complexion is a struggle — just ask any model. Of course, amazing skin is often part of the job description, but it's not just down to miraculous genetics. They rely on great skin care routines to keep their skin looking runway-ready. And when you consider the fact that they're constantly getting tips backstage from makeup and skin care pros, it makes sense that they're basically experts on the topic. They've definitely learned a few tricks to keeping the glow up 24/7 — and we're here to spill the beans.

While many of us might notice a little dip in our mood during the winter months, some of us experience a mood shift that's a bit more drastic. It's called Seasonal Affective Disorder (SAD), commonly referred to as the winter blues, and is classified as a type of major depressive disorder where episodes of depression occur around the same time each year — usually in the winter months. "SAD is more common in women than men and the prevalence rates range from 9.7 percent in New Hampshire to 1.4 percent in Florida," says A.J. Marsden, Psy.D., an assistant professor of human services and psychology at Beacon College in Leesburg, Florida. "These rates support one theory as to what causes SAD, and that is the lack of sunshine and, more specifically, the lack of vitamin D that might bring about mild to moderate episodes of depression."

Confession: since I was a kid, I've had a terrible fear of the dentist. Though I always had kind, patient doctors, the mere idea of sitting in the chair, letting them dig through my mouth was enough to send me into full-on panic mode. I grew brave enough to make — and meet — appointments without my parents once I became an adult, but the anxiety always crept in. It didn't help that after doing seven months of Accutane, I found myself with a dozen cavities and needing a few root canals, thanks to extreme dry mouth. After spending far too much money (since insurance covers next-to-nothing) on dental work, I was excited for a year abroad when I wouldn't have to worry about my pearly whites. That is, until six months later, and an infection under one of those root canals spread, and I had to have a tooth pulled...in Thailand. An army of friends supported me (and one faithful friend held my hand for three hours) but the experience made my dentophobia deepen.

Searching for something to give your lashes a little extra oomph? A great fiber mascara my just be in order. Fiber mascaras are typically made with, well, fibers. The concept may sound counterintuitive, but these little fibers cling to lashes and help build both length and volume, without heaviness or clumping. Think of it like applying baby powder between coats of mascara — they add extra bulk and definition and really amp up the drama.