The general cause of itchy, dry skin might seem like a no-brainer: It's a lack of moisture. But where does that lack of moisture come from? “Dry skin is caused by an impaired skin barrier and dysfunction or deficiency in the necessary healthy fats in the top layer of the skin,” says Shari Marchbein, MD, a board-certified dermatologist with Downtown Dermatology in New York City. Normally, the top layer of skin is made up of dead cells and natural oils, which help trap moisture to keep the skin soft and smooth, according to the University of Iowa Hospitals and Clinics. But if there’s not enough water in this top layer of cells, which can happen if the protective oils are diminished, dry skin could result.

In most cases, experiencing dry skin, or xerosis cutis, isn’t a big concern. According to MedlinePlus, it’s extremely common, can occur in people of all ages, and can pop up anywhere on the body, from the hands and face to the legs and stomach. Dr. Marchbein says that dryness can make the skin red, flaky, or itchy, which can be uncomfortable, but beyond that, there’s usually not much to worry about.

But sometimes the dryness will be severe and may indicate an underlying skin issue or health condition (more on that below). If the dryness is so severe that it interferes with your ability to work or sleep, if the skin becomes cracked or bleeds, or if it doesn’t seem to be responding to prescription treatment, be sure to visit your primary care doctor or a board-certified dermatologist, suggests Harvard Health.

Your first thought when you experience dry skin may be to pile on moisturizer. And while that’ll help and you’ll likely see changes within a few minutes, that’s a temporary solution. It may be more beneficial to get to the bottom of what’s causing the dryness in the first place. You might be surprised by what you find — some skin dehydrators lurk in surprising places.

If you're looking for remedies for dry skin, check this list first to find out whether one of these offenders may be to blame, and find out how experts suggest you combat these dehydrators. You should see improvements within a week or two of caring for your skin properly, according to Harvard Health.

1. Fragrance Has the Potential to Cause Skin Irritation

"Fragrance has a tendency to irritate dry skin or make it worse, so avoid deodorants and skin-care products that are filled with fragrance," says Amy Forman Taub, MD, a clinical assistant professor of dermatology at Northwestern Medicine in Lincolnshire, Illinois. That’s because fragrance is a common source of allergic contact dermatitis. It could take several exposures for the skin to react, or you might see a reaction the very first time, according to the Cleveland Clinic.

Check the ingredients list for the word "fragrance," and remember "fragrance-free" is your friend. Body lotions and creams may do more harm than good when packed with perfumes. Read labels carefully. Lavender oil and other botanical oils have natural preservative properties and are used in cosmetics that may still be labeled “fragrance free.”

2. Soap May Sap Moisture From the Skin and Scalp

“Many soaps, detergents, and shampoos subtract moisture from your skin and scalp, as they are formulated to remove oil,” says Gretchen Frieling, MD, a board-certified dermatopathologist in Newton, Massachusetts. It’s important to carefully choose face washes, body washes, and laundry detergents. Using only moisturizing body wash is better than a harsh bar soap, says Jeffrey Benabio, MD, a dermatologist at Kaiser Permanente in San Diego. Joel Schlessinger, MD, a dermatologist in Omaha, Nebraska, warns against harsh detergents — and even fabric softeners — if you have dry skin. Instead, look for gentle laundry soaps like Seventh Generation Free and Clear.

3. Genetics Can Affect Your Risk for Dry Skin

Chalk it up to another thing you can blame on your mom and dad: Researchers say that dry skin can be inherited. According to a study, mutations in genes that control the production of the protein filaggrin, which plays a role in forming and hydrating the skin barrier, can cause several skin conditions. People with these mutations, estimated to be about 10 percent of the population, suffer drier skin and have a greater chance of developing eczema. Atopic dermatitis is a common type of eczema.

If you've always had dry skin or if it runs in your family, it's essential that you're diligent with daily moisturization. "Look for ceramides and lipids in moisturizers, which help build and reinforce the skin barrier," says Joshua Zeichner, MD, the director of cosmetic and clinical research in dermatology at Mount Sinai Hospital in New York City.

4. Hard Water Can Prevent Moisturizers From Absorbing

When tap water contains a high concentration of minerals like magnesium and calcium, it's known as hard water, according to the U.S. Geological Survey. Those minerals can leave a film on skin that causes dryness. "Heavy metals turn the oils on skin into a thick substance that plugs glands, aggravates conditions like acne and rosacea, and prevents moisturizers from being absorbed into the skin," says Dennis Gross, MD, a board-certified dermatologist and dermatologic surgeon in New York City. Investing in a home filtration system, whether a whole-house treatment or one that attaches to the faucet, can help, according to the Centers for Disease Control and Prevention. Dr. Gross also recommends adding skin-care products that contain vitamins A and C to your routine because they counteract the coating deposited by hard water.

5. Acne Medications and Retinol Speed Skin Cell Turnover, Causing Dryness

Salicylic acid can be great at treating acne, but it may also dry out your skin when you first start using it, according to MedlinePlus. Dryness is a common side effect of retinol, too, and it happens because retinol loosens the connection between cells on the skin’s surface, according to a study published in August 2017 in The Journal of Clinical and Aesthetic Dermatology. The good news is that you don't have to give up these skin-care saviors, though cutting down on their use may deliver results without irritation. "Reduce the frequency of use from every day to every other day or so, make sure you choose a gentle cleanser that isn't compounding the issue, and ask your dermatologist for a less drying prescription if necessary," Dr. Forman Taub says.

The best frequency will depend on your specific skin type, according to the American Academy of Dermatology. Take burning, peeling, and flaking as signs you need to stop using the product, Dr. Frieling says. “This is not something to play guessing games with and use trial and error,” she notes. Schedule an appointment with your dermatologist and bring the product with you so the doctor can evaluate it and make sure it’s right for your skin.

6. Dry Air, Indoors or Out, Can Increase Symptoms of Dry Skin

Sometimes the air inside can be as punishing on your skin as the air outside. Forced air, especially heat, can draw humidity levels down, making skin feel dry and itchy, Frieling says. Luckily, you don’t need to suffer with dry, itchy skin all winter: A humidifier can help restore moisture to the air in your house. It’s best to set yours between 30 and 50 percent humidity, according to the Cleveland Clinic. "Additionally, it's a good idea to keep a mild — 1 percent — hydrocortisone cream on hand. Use it early if you see signs of chapped or dry skin," Dr. Schlessinger says. Hydrocortisone, which sometimes requires a prescription, reduces swelling, redness, and itching and helps heal and soothe dry, chapped skin and speed its healing, according to MedlinePlus.

RELATED: What Causes Chapped Lips?

7. Zealous Handwashing Can Lead to Redness and Irritation

"Some people with dry skin just wash their hands constantly," Forman Taub says. That won’t help the dryness because too much washing can lead to dry, cracked skin, according to Piedmont Healthcare. This can be a big issue for people who work in industries that require frequent handwashing, such as health care. To mitigate the drying effects of your sanitary habit, use lukewarm water (hot water strips your skin’s moisture), avoid alcohol-based soaps, and blot your hands dry instead of rubbing them with a paper towel, according to EveryNurse. Ointments tend to be thicker than moisturizers, so keep an ointment (such as Aquaphor) on hand and apply after each wash.

8. Long, Hot Showers Can Contribute to Skin Dehydration

It might be tempting to stand under the steaming-hot water for an extended period of time, especially during the cold months. But the practice could end up creating issues with your skin. “Taking long and steaming showers or baths can dry out the moisture in your skin,” Frieling says. Marchbein says to limit showers to no more than five minutes and to keep the water temperature warm, not hot. Afterward, apply a moisturizing cream within one minute of getting out of the shower, Marchbein adds. Moisturizers work best on damp skin, according to MedlinePlus.

9. Aging Can Increase Skin Dryness

Dry skin tends to become more of an issue as people get older. The Mayo Clinic notes that adults ages 40 or older are at an increased risk of experiencing dry skin, and it affects about half of the individuals in this age group. “As we get older, our skin produces less oil and gets drier,” Frieling says. For women, it could also be due to the hormone changes associated with menopause, according to Penn Medicine. The fix? Moisturize every day (or multiple times a day if needed), recommends the American Academy of Dermatology. Marchbein says to look for a moisturizer that contains ceramides, humectants (such as hyaluronic acid or glycerin), and petrolatum. These ingredients help replenish lost moisture and quickly repair the skin barrier, she says.

10. Certain Medical Conditions Can Cause Dry Skin

Skin issues such as psoriasis and eczema can make your skin more prone to dryness, Frieling says. But dry skin could also indicate something seemingly unrelated, such as diabetes, hypothyroidism, malnutrition, kidney failure, or Sjögren's syndrome, according to Harvard Health and Penn Medicine. So how might you know if the dryness is the result of something run-of-the-mill like the weather or something more serious? Frieling says to be on the lookout for inflamed areas, crusting, intense itchiness, hyperpigmentation, and rough, flaky, or scaly patches on the skin and take those as a hint it’s time to visit a doctor. Once you’ve nailed down the root cause for the dryness, your doctor can help you determine the proper treatment.

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