Retinol is by far the gold standard of anti-aging. Nearly three decades of medical research proves it packs a serious wrinkle-reducing punch. This vitamin A derivative is able to spark cell turnover and, as a result, kick-start the production of new skin cells while spurring an increase in fresh collagen. Skin is kept looking radiant and evenly toned by warding off the excess production of hyperpigmentation and fine lines, both now and down the road. There are two forms of this anti-aging powerhouse — over-the-counter retinol and prescription retinoid. The latter is more potent, and therefore, possibly more irritating (the most common not-so-pretty side effects of retinol include redness and flaking, as well as increased sensitivity to the sun). Dermatologists recommend baby-stepping into a retinol-based skin-care — starting with a low dose and increasing over time. Look for formulas that also have skin-soothers such as hydrating hyaluronic acid to help lessen irritation.