Forget tripping and spraining an ankle! High heels cause much more than just foot and ankle pain. New studies show that heels are a big cause of ingrown toenails (ick!) Ingrown toenails occur when toes are squished so that the big toenail grows into the skin. This can cause an infection, sometimes causing your to have to the remove the entire nail. Heels can even reshape the calf muscles and tendons, shortening them so that women who wear heels often may find it uncomfortable to walk flat-footed. More reasons to never take off those comfy trainers :) For heel lovers, just try to limit your time in heels, especially on days with walking and standing. Another interesting idea is to outline your feet on cardboard and take the cut-out when going shoe shopping. If the cardboard can't fit into the shoe without being scrunched, neither can your feet!