8 Confusing Skin Questions — Answered

The answers to all of your skin questions.

1. Is a $10 moisturizer just as good as a $50 one?
Yes. For basic moisturizer, price doesn't matter. "Hydrating ingredients aren't expensive. What you're paying for in a pricey moisturizer is packaging, fragrance, and the nice lady at the counter selling it to you," says Los Angeles dermatologist Jessica Wu, M.D., author of Feed Your Face. Just check the ingredients for tried-and-true hydrators like glycerin, hyaluronic acid, and panthenol. Our pick: Olay Age Defying Instant Hydration Day Cream ($10, drugstores). Save your money for serums or night creams; ingredients like peptides and retinol can drive up their cost (by $25 or more).

2. Will using a face oil make me break out?
No; unless you're acne-prone. "If your skin is already oily, using an oil can clog pores, which ups the potential for breakouts," says New York City dermatologist Debra Jaliman, M.D., author of Skin Rules. This applies for both mineral oil and plant-based oils such as sunflower and olive. However, if you have dry skin, an oil can help lock in moisture; use it under or in lieu of a moisturizer. One option: Lumene Complete Rewind Intensive Recovery Beauty Oil ($30, drugstores).

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3. Are dark circles caused by lack of sleep?
No. Too little shut-eye can make them look worse, but they're influenced by multiple factors: how thick undereye fat pads are, how thin skin is, and how superficial blood vessels are. Hence, some people are likelier to have them than others, explains Dr. Wu. "When you're tired, your blood vessels dilate and eyes get puffy, creating shadows. This makes dark circles more prominent, but it's not the cause," she says. A cover-up, like Revlon PhotoReady Concealer ($10, six shades; drugstores), is the best fix.

4. Will an over-the-counter brightening cream get rid of my dark spots?
No. A lightener or brightener can't fully eliminate spots (which are too deep in the skin), but it can fade them a lot, especially if they are newly formed. One to try: L'Oreal Paris Youth Code Dark Spot Correcting & Illuminating Serum Corrector ($25, drugstores) - a 2013 Anti-Aging Award winner. An in-office laser can eradicate spots, but even that method isn't foolproof: "If you're not diligent about daily sunscreen afterward, that hyperpigmentation will come right back," says Tamella Buss Cassis, M.D., a dermatologist in Prospect, KY.

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5. My skin is really dry. Is moisturizing enough to fix it?
No. When you've reached the scaly, itchy stage, using lotion alone won't cut it. "If you don't exfoliate first to get rid of that layer of dead skin, moisturizer won't penetrate," says Dr. Jaliman. Just don't overdo it, or you may irritate your skin and make matters worse. Use a scrub once or twice a week (avoid salt-based ones, which can be drying), and then apply moisturizer immediately. Try: Nuance Salma Hayek Macadamia Nut Exfoliating Body Cleansing Scrub ($9).

6. Since I do my own manis and pedis at home, am I safe from nail infections?
No. While DIY exposes you to less risk than getting a nail job in a salon, using dirty tools can still lead to a bacterial infection, which causes red, swollen, and painful skin around the nail bed, says Dr. Cassis. Even a seemingly innocuous nail file can harbor bacteria. Choose a crystal or stainless steel option (either can be washed), and wipe all your tools with rubbing alcohol or wash them in warm, soapy water after each use.

7. Do I need to wear sunscreen if my makeup has an SPF?
Yes. You can't rely on makeup alone. "To get adequate sun protection, you have to apply an even coat all over your face," says Dr. Cassis. "If you just put on foundation wherever you need coverage, you won't get an even layer." Plus, makeup sits on skin's top layer and wears off quickly, whereas a moisturizer's chemical sunscreen is absorbed by skin, making it more effective. Use a moisturizer with SPF 30, such as First Aid Beauty 5 in 1 Face Cream ($38) 365 days a year.

Related: What's Missing from Your Weekly Beauty Routine

8. If I incorporate antioxidants into my diet, do I need to apply them topically, too?
Yes. The antioxidants meant to be slathered on skin protect its surface from environmental assaults like pollution, smoke, and the sun, which contribute to the development of wrinkles, spots, and other signs of aging; ingesting antioxidants delivers them deeper into the skin. If you do both, you'll get anti-aging benefits for all layers of the skin, explains Dr. Wu. Consider adding vitamin C to your skin-care routine - it does double duty, fighting free radicals and stimulating collagen production. Try applying a serum, such as PCA Skin C-Quench Antioxidant Serum ($74), in the morning, underneath your moisturizer and/or sunscreen. And, diet-wise, load up on brightly colored berries: They're filled with anthocyanins, antioxidants that may help prevent collagen breakdown.

-Melanie Rud Chadwick

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