When you were young, your parents always told you to eat your fruit and veggies. When you grew up, you learned that the wonder substance contained inside those foods--vitamin C--also offered a host of benefits when applied topically. And now, of course, the counters are teeming with C-enriched skin-care products; problem is, if the vitamin isn't curated its purest form and formulated at precise concentrations, its efficacy is greatly reduced (sort of like when you overcook your veggies and remove their skins). Enter SkinCeuticals's AOX+ collection--three innovative skin serums and one pioneering gel that combine pure vitamin C (also known as L-ascorbic acid) with ferulic acid (the potent antioxidant centerpiece of the brand's classic C E Ferulic).

The lightweight serums come in three concentrations formulated for various skin types (10, 15, and 20, shown; from $60 to $95; skincarerx.com). Much like vitamins, they're designed to be used once a day (simply apply four to five drops to the face, neck, and chest). Although you won't see instant changes, the serums start working immediately to neutralize free radicals, guard against environmental damage, stimulate collagen production, and prevent premature aging. And best of all, over time, the results are impressive: Redness and hyperpigmentation are reduced; fine lines and wrinkles diminished; and damaged skin looks healthier. The Eye Gel AOX+ ($42) offers similar boons for the delicate skin around peepers, smoothing out crow's-feet, decreasing puffiness, and restoring a smoother, more radiant appearance. --Terra Cooney