If a nutrient deficiency is truly the reason for your brittle nails, your doctor might suggest addressing your diet first, says Dr. Manning. But if your doctor gives you the green light to take a supplement as well, there is some research showing that certain kinds are beneficial for brittle nails.
While some studies indicate that biotin supplements strengthen brittle nails, these studies are small and of lower quality. More research is needed to conclusively show a connection between biotin supplements and brittle nails.
“Collagen is made of amino acids that help form keratin, so it makes sense biologically,” says Cristina Del Toro Badessa, MD, a board-certified physician with Artisan, a plastic surgery practice in Atlanta. “I often suggest it as part of a holistic nail health plan, especially since it may also benefit skin and joint health. It’s not a guaranteed fix, but it’s safe, and many of my patients do report stronger nails after a few months.”
If you want to take a supplement, talk to your doctor first.
“In my experience, it’s safe to try a moderate dose of biotin short-term, particularly if we’ve ruled out more serious causes like iron or thyroid issues,” says Dr. Del Toro Badessa. “I also remind patients to let their doctor know if they’re taking it, since high-dose biotin can interfere with lab tests, including thyroid and cardiac markers.”