Using too many products at once
If a new moisturizer is good, then the combination of a new serum, toner, and night cream must be better - right?
Not so fast. If your skin gets irritated after you use a handful of new products, you won't know what's causing the problem and assume they're all irritating. Instead, "start with one at a time, and integrate a new product every two weeks," says Dr. Jacob. That way, you'll be better able to identify what's aggravating you, or know what combination of them makes your skin go haywire. Plus, you'll also save some cash by buying only what you need.
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