Symptom: Puffy eyelids
What it might mean: Swollen eyes may be from something as simple as skimping on shut-eye one night.
"Sleeping on your stomach can also cause fluid accumulation around the eyelids," says Potter. But if they look itchy, red, and scaly you may also have a seasonal allergy or be suffering from an allergic reaction. "The eyelids are covered with the thinnest skin on your body and will often show an allergy before any other place," adds Peredo. Common allergies include fragrances, dyes in beauty products and clothing, and formaldehyde (a preservative in some creams, shampoos, and nail polish). Your dermatologist can run an allergy patch test to determine what ingredient is setting off your symptoms.