As a beauty editor, I've developed a bit of an obsession with hair health. We used to think thinning hair was something you had to accept, but today's treatments and ingredients are changing that. And while I've spent plenty of time researching solutions for scalp hair loss in both men and women, I knew very little about another area where many of us notice thinning as we age: our eyebrows and eyelashes. 

Curious to learn more, I spoke with dermatologist Dr. Bonnie Hodge about the biology behind brow and lash health, why elastin- and peptide-based formulas are generating so much interest, and whether the science behind them actually holds up. Here are my four takeaways from our conversation.