Retinol serums are being reported as a highly effective treatment for signs of aging, with various outlets recommending them for smoother, firmer skin. Some sources have tested numerous retinol serums and compiled lists of the best ones for tackling issues such as acne, wrinkles, and hyperpigmentation. However, not all experts agree on the value of retinol, with at least one dermatologist suggesting that affordable alternatives may be just as effective.