From general fatigue to possible Parkinson's disease, skin, hair, and nail conditions can be symptoms of a range of ailments
Though skin is on the outside of your body, it can be a surprisingly clear window to what’s happening on the inside.
"You can tell a lot about somebody by looking at their skin," says Bruce Brod, MD, FAAD, a dermatologist on faculty at the University of Pennsylvania in Philadelphia. Perhaps most obviously, the state of your skin can suggest your living habits to a dermatologist’s trained eye.
"One of the first things a dermatologist can tell by looking at someone is how much outdoor exposure they’ve had by the appearance of sun damage for their age," says Dr. Brod. "Things like wrinkles, spots, uneven pigmentation, and loss of elasticity."
Skin may also be a giveaway that people are sleep deprived. "Droopy, saggy, dark circles under the eyes can be a clue to fatigue," says Steven Daveluy, MD, FAAD, a dermatologist with the Wayne State University School of Medicine in Dearborn, Michigan.
Skin can even tell dermatologists if people are drinking enough fluids to stay hydrated. "One of the signs of dehydration is sunken-looking skin around the eyes," says Dr. Daveluy. "Dry skin can also indicate dehydration."
And smokers’ skin often gives away their habit. "The skin of smokers is often more pale or sallow in color, and they’ll have wrinkling around the lips," says Dr. Brod.
But even more than revealing lifestyle habits, skin can also help doctors diagnose many illnesses. Your board-certified dermatologist can help discover whether the following symptoms may be due to something more serious.
Dry, itchy skin
It’s not uncommon for skin to feel dry or itchy, especially in the winter. Keeping your baths and showers short and moisturizing while your skin is still damp afterward can usually keep this condition under control. People with chronic skin conditions like atopic dermatitis (eczema) experience these symptoms more often and more severely. "But there’s a subset of patients who itch because of an underlying disease," explains Dr. Brod. Diabetes, for example, can make the skin more prone to itching, as can lymphoma. Opioids and other medications can also cause itching. Thyroid disorders may cause skin to become dry. "Dermatologists have the training to be able to know when to do a blood test and evaluate a patient more thoroughly," says Dr. Brod.
Constant handwashing and using hand sanitizers with alcohol during the coronavirus pandemic can take a toll on your hands. Moisturizing hand creams or ointments can usually take care of this common problem. But, sometimes the problem isn’t so common. "A condition called dermatomyositis can mimic hand dermatitis caused by irritation or overwashing, with red patches on the back of the hands," says Dr. Brod. "Dermatomyositis is an inflammatory, autoimmune disease similar to lupus." A dermatologist can tell when irritated-appearing hands are really something more.
Seborrhea is the medical name for common dandruff on the scalp (and sometimes around the nose). It can usually be treated with medicated shampoos or prescription treatments. "But even dandruff can be a clue to underlying illness," says Dr. Brod. "Patients with neurological conditions like Parkinson’s disease or stroke are more prone to developing severe seborrhea." People with HIV are also more prone to seborrhea.
Breakouts are normal during adolescence, and they often persist into adulthood. Wearing a face mask can also cause acne to flare. "But new acne, or really severe acne you didn’t have before, can sometimes indicate an underlying hormonal abnormality, such as polycystic ovary syndrome (PCOS) in women," says Dr. Daveluy.
Color changes to the skin can sometimes indicate underlying illness. "Skin sometimes looks gray, sallower, in people with underlying chronic illness," says Dr. Brod. Yellowish- or orangish-looking skin can be a sign of kidney or liver disease. "And brown or tan spots on the shins can be a sign that blood is not circulating well, and may eventually progress to ulcers," says Dr. Daveluy.
While skin color changes can be important clues for dermatologic diagnoses, Dr. Brod says that these clues may appear differently in someone who has skin of color. For instance, rashes may appear darker or have a purple hue. That’s why it’s important to see a board-certified dermatologist, as they have the expertise and training to recognize and diagnose changes in skin in people of all colors.
Small bumps around the eyes
Small yellow bumps that can show up around the eyes or nose are called xanthelasma, and they’re made of cholesterol deposits. "In some people, it’s a sign that you have high cholesterol," says Dr. Daveluy. "But in about half of people, it’s not." Having the bumps, though, is a sign that you should have your cholesterol checked.
There are a lot of reasons why your skin might break out in a rash. Common rashes include contact dermatitis—a reaction to something your skin touches that can usually be easily treated with topical therapy and avoiding the substance that triggered the rash. "But sometimes even rashes that are easy to treat can indicate changes to overall health," says Dr. Daveluy. Other times, rashes appear as a symptom of skin diseases that can affect your overall health. Having psoriasis, for example, increases the risk of having heart disease and other conditions. And, of course, there are distinctive rashes like the target-shaped rash of Lyme disease and the butterfly rash across the face that many lupus patients develop.
"There are a few things that might be clues that your rash is more serious," says Dr. Daveluy. "If it doesn’t respond to treatment, and if it’s affecting more than your skin—for instance, if you have joint pains or fever—that may indicate that there’s something going on internally."
If you notice a change in your skin, there’s no need to panic.
Most skin disorders don’t signal serious illness and are treatable. But do schedule an appointment with a board-certified dermatologist to find out what’s going on. Your skin may be trying to tell you something.
Look for the designation FAAD (Fellow of the American Academy of Dermatology) to be certain you are getting care from a board-certified dermatologist. Visit the AAD’s Find a Dermatologist tool to find a Fellow in your area.
Related AAD resources
Last updated: 5/27/21