A serum is a skincare treatment formulated with a high concentration of active ingredients. Unlike moisturizers and facial oils, serums have a thin, watery-like consistency that absorbs quickly and penetrates deep below the layers of the skin. There are many different kinds of serums you can incorporate into your routine depending on your skin type, concern, and goals.The Benefits of Serum for Skin The main benefit of a serum is to treat a specific skin concern, such as acne, dullness, or aging skin. While cleansers are rinsed off and SPF sits on top of the skin to defend it against the sun, serums can sink deep into pores to deliver active ingredients and skin-changing results. A serum’s formula will vary depending on the ingredients used. For dullness, hyperpigmentation, and dark circles, you’ll typically see ingredients like vitamin C and niacinamide (both found in our Stroke of Brilliance Brightening Serum). Serums for controlling breakouts, unclogging pores, and treating oily skin (like Just Breathe Clarifying Serum) may use a BHA, such as salicylic acid, or zinc. Hyaluronic acid is often a hero in hydrating serums, while the best face serum for aging skin usually incorporates retinol, peptides, or ferulic acid.