Ask the doctors: Dark circles? Blame genetics, lifestyle or health issues

Q: What causes dark circles under the eyes? I have always had areas of darker skin under my eyes, but as I'm getting older, it has been getting more noticeable. Could it be something to do with sleep, or with my diet?

A: Having dark circles under the eyes affects people of all ages. It can cause someone to be perceived as being tired, sad or even ill. In most cases, it's a cosmetic issue and doesn't pose a threat to health. It is possible, though, for the appearance of darker skin in the area under the eyes to arise from an existing health problem. This can include asthma, allergies, poor circulation, hormonal shifts, malnutrition, anemia and diseases that affect the liver or kidneys. Certain medications can also contribute to the appearance of darker skin beneath the eyes.

When dark circles don't arise from health issues, other factors may be at play. A primary cause has been found to be heredity. That is, the genetic information someone inherited from their parents causes the skin beneath the lower eyelid to be darker than the surrounding skin. If your parents or siblings have darker skin beneath their eyes, it is more likely that you will have or develop it as well. Facial structure, where someone has a deep or pronounced depression beneath their eyes, can cause a shadowing effect. So can sudden or significant weight loss and age-related changes to the face. Lifestyle issues such as having a poor diet, not getting enough sleep and chronic or excessive tobacco or alcohol use can also play a role.

Treatment options depend on the specific cause. When hyperpigmentation is present, a class of drugs known as retinoids can be helpful. These are derivatives of vitamin A. They fall into a category known as cosmeceuticals, and they can have some side effects. Retinoids have an exfoliating effect on skin. They can cause dryness and increase sensitivity to sunlight. Another popular cosmeceutical is hydroquinone, which interferes with melanin production. It can cause irritation, inflammation and, in some people, an allergic reaction.

Pulsed light in the form of lasers is increasingly used to treat dark undereye circles. These treatments can be costly and, depending on the specific type of laser, also come with potential side effects and complications.

When dark circles do not arise from genetics, lifestyle changes can help. None of these are revolutionary — we know you've heard them all before. But the list gets repeated because, when adhered to, they can make a difference. Make sure to get enough sleep. Limit alcohol and avoid tobacco. Watch your intake of salty foods, particularly ultra-processed foods, which contribute to swelling. The skin beneath your eyes is thin and delicate, so be gentle. Rubbing your eyes can stretch the skin and damage the fragile capillaries that supply food and oxygen to the underlying tissues. Makeup and concealers are also tried-and-true options.

Whatever the approach, stay realistic. You are lessening the appearance of dark circles, but probably not eliminating them.

Cellulitis and cellulite are not the same thing

Q: My husband and I help my aunt with doctor visits. She has a persistent wound on her foot and was diagnosed with cellulitis. She has confused it with cellulite and isn't taking it seriously. Can you offer some information so we can help her understand what's going on?

A: Although "cellulite" and "cellulitis" sound similar, they are two very different conditions. Cellulite is the term used when the layer of fat and tissue that lies just beneath the skin develops a lumpy, bumpy appearance. People are sometimes bothered by how cellulite looks, but it doesn't pose a threat to health.

Cellulitis, on the other hand, is a type of bacterial skin infection. In most cases, it is easily addressed with antibiotics and appropriate wound care. When left untreated, though, it can lead to serious health problems.

Cellulitis can occur when a breach in the surface of the skin allows bacteria to enter and penetrate the deeper layers of tissue. This may be through a wound, as has occurred with your aunt. However, the point of entry can be as small as a scrape or cut, a crack in dry skin or even an insect bite or rash. These openings make it possible for bacteria to get past the protective barrier of the skin and infect the tissues below. The two most common causes of cellulitis are strep (streptococcus) or staph (staphylococcus) bacteria.

People with weakened immune response are at greater risk of developing cellulitis. This can be due to a disease, such as diabetes, lupus or AIDS; the result of immunosuppressive medical treatment; or older age. Being overweight or obese, having lymphedema and living with an inflammatory skin condition, such as psoriasis, can also increase risk.

Symptoms of cellulitis include warmth, redness, swelling, tenderness or pain in the affected area, fatigue, fever, muscle aches or joint pain, swollen lymph nodes and inflammation that spreads rapidly. The condition is diagnosed with a physical exam, which often includes a blood test and lab cultures.

Treatment typically includes the use of antibiotics and, if needed, pain medications. Vigilant wound care is also important. Because bacteria are increasingly resistant to antibiotics, it is important to track the response to treatment. Resting and keeping the wound elevated to ease swelling are also helpful. If an infection doesn't respond to treatment, it can be necessary to switch to another antibiotic.

As we mentioned, cellulitis that goes untreated or is poorly managed can lead to complications. It is possible to develop abscesses or open sores, which can become chronic. Cellulitis itself can become recurrent if not adequately addressed.

There is also the risk that the bacterial infection will reach the blood and travel throughout the body. The danger here is a serious and life-threatening condition known as sepsis. This is a powerful overreaction by the immune system to the presence of infection. The scope of the immune response in sepsis can lead to tissue and organ damage, organ failure and even death. If your aunt continues to ignore her treatment plan, please consider asking her doctor for assistance.

• Dr. Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr. Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health. Send your questions to askthedoctors@mednet.ucla.edu.