6You have Raynaud’s.
woman and doctor taking her blood pressure looking at the screen, health questions after 50
If you notice “indentations that run across the nails”—called Beau’s lines, according to the Mayo Clinic—you could have Raynaud’s phenomenon, a condition in which blood supply to the extremities becomes limited in the face of stress or cold.
Talk to your doctor if you notice these lines on your fingernails, because, though there is no cure for Raynaud’s, there is medication that can help restore blood flow in severe cases. And for some fascinating things about the stuff that keeps your body running, check out 20 Amazing Facts About Your Blood Type.
Woman holds pregnancy test in hands, what it’s like being a teen mom
“During pregnancy the growth rate of nails is increased,” Rich noted in her paper. That’s because, as The Nemours Foundation explains, all those extra hormones coursing through your veins during pregnancy impact the strength and length of your nails.
8You have an allergy.
Woman sneezing from allergies
While many people believe that a calcium deficiency presents itself as those little white marks on your finger and toe nails, that’s not the case, according to Andrew Weil, MD, founder and director of the Andrew Weil Center for Integrative Medicine at the University of Arizona.
On his website, Weil explains that these marks, called leukonychia, are either a sign of an injury to the base of your nail (which could’ve happened up to six weeks prior), or they can also be the result of an allergic reaction to nail polish or nail hardeners. “It can take more than eight months for nails to grow out completely so the spots may be around for a while,” he notes.
9Your thyroid isn’t functioning properly.
female doctor touching the throat of a patient in the office
Your dry, brittle nails may not be your favorite thing to look at, but that doesn’t mean you should ignore them. According to the American Academy of Dermatology (AAD), “thick, dry, and brittle [nails] with visible ridges” can be a sign of thyroid disease. So, before you focus on your aesthetic problem, be sure to rule out this serious health issue.
10There’s something wrong with your lungs.
doctor holding up an x ray of lungs
If you’re worried there’s something wrong with your lungs, your nails could be your first step toward figuring it out. As researchers from York Hospital in Pennsylvania wrote in a paper in American Family Physician, clubbing of the nails—in which the tips of the fingers enlarge and the nails curve downward around the fingertips—”often suggests pulmonary disease.” And for more helpful information delivered straight to your inbox, sign up for our daily newsletter.