Once upon a time, wrinkles were seen as the only marker of an aging face. Now it’s understood that a loss of volume due to collagen depletion also contributes to a less-than-youthful-looking visage. Dermatologist Fredric Brandt goes after both problems with Dr. Brandt Collagen Booster. The silky serum instantly smooths lines with fern extract, prevents collagen breakdown with peptides, and employs amino acids to encourage the formation of new collagen. $75; at Sephora.