Peptides

How they work: Peptides are chains of amino acids that are the building blocks of proteins in the skin. They can penetrate the skin’s top layer and send signals to cells. Peptides are one of the most promising skincare discoveries as they strengthen connective tissue, giving skin more elasticity.

You need them if: Your skin isn’t looking its best. They’re also particularly good if you’re an outdoorsy type and your skin is a little weather-beaten.