"You can detect everything from diabetes to nutritional deficiencies just by examining the feet," says Jane Andersen, Doctor of Podiatry Medicine and president of the American Association of Women Podiatrists and a spokeswoman for the American Podiatric Medical Association
For example, a suddenly enlarged, scary-looking big toe is probably gout. Gout is a form of arthritis (also called 'gouty arthritis') that's usually caused by too much uric acid, a natural substance. The built-up uric acid forms needlelike crystals, especially where there is low body temperatures. The coolest part of the body, farthest from the heart, happens to be the big toe. "Three-fourths of the time, you wake up with a red-hot swollen toe joint as the first presentation of gout," says Dr. Andersen.