Studies indicate that collagen supplements can support healthy nail growth.* One study found that when patients took collagen daily for 24 weeks, their nail health improved, including better growth rates, reduced breakage, and improved appearance. The same goes for biotin, a form of vitamin B that is often used in hair growth supplements. Biotin has been shown, even in those who aren’t dealing with thyroid issues, to support thickness and firmness of nails. If nail growth is a regular issue for you, consider daily supplementation—and best yet, find an option formulated with both.