Treating the underlying condition often can save your nails-and maybe even your life. So if you spy something new or unusual on the ends of your digits, check in with your primary care doctor or a dermatologist, she advises. That’s because diseases that affect your whole body can change the blood flow, growth patterns, or shape of your fingernails and toenails in ways you may notice long before any other symptoms, says Chris Adigun, M.D., a board certified dermatologist and nail specialist in Chapel Hill, N.C. Related: The Men’s Health Better Man Project-2,000+ Brilliant Tips for Living an Awesome, Healthier, Happier Life “Certain nail changes can indicate issues with the kidneys, infections of the heart, anemia, lung disease, and even exposure to certain poisons.” “Your nails can tell a tremendous amount of information about your general health,” says Dana Stern, M.D., a dermatologist and nail specialist in New York City. Your eyes may offer a glimpse of your soul-but for a view of your internal organs, check your fingers and toes instead.