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Don't Need It: A Cleanser That Claims to Do More Than Clean
"Cleanser stays on your face for about six seconds—no anti-aging ingredient can affect your skin in six seconds," says Boston dermatologist Ranella Hirsch, MD. Almost every skin doctor we know washes her face with a basic drugstore cleanser—they're simple, cheap and do what a cleanser should: clean your skin. Save your money for skincare products that you don't immediately wash down the drain. (Hirsch's current favorite cleanser: Basis Cleaner Clean Face Wash, $6; drugstores.)
Fancy cream with a spoon

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Don't Need It: A Cream That Comes with a Tiny Spoon
Moisturizers with triple-digit price tags and fancy trappings—layers of elegant wrapping, glass jars that weigh more than a newborn, Lilliputian gold spoons—do the same job as the basic drugstore versions. "The purpose of any moisturizer is to seal in moisture, keeping your skin supple and smooth," says San Diego dermatologist Jeffrey Benabio, MD. "Whether the moisturizer costs $200 or $20, it uses the same basic ingredients to do that."
Woman applying neck cream

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Don't Need It: A Neck Cream
The cream you use on your face at night is likely rich enough to soften and smooth the skin on your neck. There's no need to invest in a separate product. However, there is one exception: If you have oily skin and use a very lightweight moisturizer (or none at all), you should get a separate cream for your neck (which has fewer oil glands and needs more hydration than your face). You don't need to buy a pricey cream marketed as a neck product, though, says New York City dermatologist Jessica Krant, MD, who recommends La Roche-Posay Toleriane Riche ($28, drugstores), which has a high concentration of skin-softening shea butter.

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SkinCeuticals Physical Fusion UV Defense SPF 50

Photo: Courtesy of SkinCeuticals

Need It: A Sunscreen
This is the only product that will prevent your skin from aging in the first place. Use it early (at least 20 minutes before you leave the house) and often (reapply every two hours if you're spending the day outside). The best sunscreen is the one that you will use consistently, so find a texture that works for you. Many moisturizers now include sunscreen; tinted sunscreens double as makeup and won't look chalky. We like SkinCeuticals Physical Fusion UV Defense SPF 50 ($60 for 125 milliliters; Don't forget to apply sunscreen on all exposed skin—which, on most days, includes your neck.
RoC Retinol Correxion Deep Wrinkle Night Cream

Photo: Courtesy of RoC

Need It: A Retinoid
Lotions or creams that contain a retinoid are your best shot at making your skin look younger. Piles of research prove that this vitamin A derivative really can undo wrinkles and discoloration caused by sun damage. At the drugstore, look for the word "retinol" in the ingredients list (the higher up it appears on that list, the better); one great option is RoC Retinol Correxion Deep Wrinkle Night Cream ($22, drugstores). A dermatologist can prescribe a stronger retinoid cream, like Retin-A or Tazorac. Retinoids can be irritating at first, so ramp up slowly until you can tolerate using one every night. You should apply a retinoid cream on your neck as well, but because that skin can be more sensitive, use it more sparingly and not necessarily nightly.

Photo: Courtesy of Aveeno

Need It: A Basic Moisturizer
So you know you don't need to spend hundreds on a moisturizer. But what do you need to look for? An effective moisturizer will contain two types of hydrating ingredients: a humectant (to draw water to the skin) and an emollient (to prevent water loss). Common humectants are glycerin, hyaluronic acid and propylene glycol; emollients include dimethicone, petrolatum and coconut oil. Look for at least one of each in the ingredients list. (Aveeno Positively Ageless Restructuring Treatment Cream, $20, and Olay Regenerist Night Recovery Cream, $25, are good bets you can find at the drugstore.) Unless your skin is oily, apply a moisturizer on top of your retinoid at night. And if your face isn't shiny in the morning, skip the cleanser and just splash your face with lukewarm water. "There's no better moisturizer than the natural oils on your skin," says Benabio. "Why wash them off?"

Next: The best $25-or-less anti-aging products