Losing that much brow hair changed the way my entire face looks, and as a result, I’ve been on a mission to grow them back with the help of the best eyebrow growth serums. Chockfull of nourishing ingredients that help condition the hair and support a healthy brow environment, these formulas can help sparse brows appear fuller and more defined over time. And brow serums aren’t necessarily about achieving bushy, oversized brows, either.