First, consider the ingredients, with a retinoid, such as retinol, being the most important. It’s “a powerhouse ingredient known to accelerate skin cell turnover, boost collagen production, and smooth out fine lines and wrinkles,” says Dr. Libby. “It also helps improve skin tone and texture and overall skin appearance.” In short, there’s little it can’t do to improve skin and give it a more youthful appearance. (The downside? It can be drying on skin, leaving it red and irritated.)

In addition to retinol—or in lieu of it, for those who can’t use retinol or tolerate it due to its side effects—another worthwhile ingredient is peptides. “Peptides act as messengers to the cells to increase collagen and elastin production, minimize the appearance of fine lines and wrinkles, and increase wound healing,” says Dr. Lin, who notes that these tend to be more gentle and don’t require an acclimation the way retinol does. Moreover, “there is also some evidence to suggest that the peptides may support the skin barrier to protect against UV damage, which can contribute to skin aging,” she says.

Retinol and peptides can take time to yield results, which is where hyaluronic acid can be especially helpful. Naturally found in skin, its supply dips with age—and restoring it through a topical product can offer an immediate improvement in skin texture. “For some, it can have a plumping effect and reduce the appearance of fine lines and wrinkles,” says Dr. Lin. “In addition, it may have wound healing properties and promote tissue repair.”

A word on collagen: Though you might see it as an ingredient, it doesn’t simply replace the collagen that gives firmness and structure to skin. “In its true form, collagen is too large of a molecule to penetrate the skin,” says Dr. Lin. And while you might find a hydrolyzed, or broken-down, version of it in formulas, it’s still unclear whether this can penetrate skin well enough to offer any true benefits. As a result, “it may be better to have ingredients that can increase collagen production instead,” says Dr. Lin. (However, collagen can have moisturizing properties, she says, so it still has use in some formulations.)