Why is my skin dry when indoor humidity is 20%?

Why does dry indoor air affect your skin?

Skin continually loses water through its surface. Low indoor humidity increases that loss, making moisture harder to retain. Flaking, itching, tightness and cracking are common signs of dry skin. Heating and air conditioning can reduce indoor humidity, so staying inside does not remove the problem. Indoor heating can leave you warm while drying the air, which is a fairly poor bundled service.134

Changes can develop during an ordinary day indoors. In a small trial involving healthy women, six hours in a heated room below 20% humidity increased facial roughness and redness, while water loss increased on the forearm. The face and forearm did not respond identically: facial oil appeared to help maintain the skin's barrier, its protective outer layer. Dry air can affect healthy skin, not just skin that already has eczema.5

Should you raise the humidity?

Yes. A humidifier adds moisture to dry indoor air and can help relieve skin dryness. A filtered, cool mist humidifier in the bedroom is one option, particularly while you sleep. For adults in their 60s and 70s, keeping indoor humidity between 45% and 60% can reduce dry, itchy skin. That makes 20% a useful clue about your environment, rather than a reason to keep changing skincare products.246

Do not run a humidifier without watching the room's humidity. Excessive humidification can cause condensation and promote mold growth. Use a humidity meter to track the level rather than judging it by how much mist you can see.14

How to keep moisture in your skin

1. 1Wash with warm water, not hot water. Hot water removes protective skin oils and can worsen dryness.
2. 2Keep baths and showers to 5 to 10 minutes. Use a gentle, fragrance free moisturizing cleanser and avoid scrubbing with a bath brush.
3. 3Pat your skin gently, leaving it slightly damp rather than drying it completely.
4. 4Apply a fragrance free cream within 3 minutes of bathing. For very dry skin, choose an ointment, which holds water in the skin better than a cream.
5. 5Reapply moisturizer throughout the day, and moisturize immediately after washing.

Choose a richer moisturizer rather than a watery lotion that dries quickly. Petroleum jelly and heavier creams are useful options in dry winter conditions. A richer drugstore moisturizer can do the job; the price tag does not hold water in your skin. Keep using moisturizer even after adding a humidifier: the two measures address the air and the skin separately.36

What else could be making dryness worse?

Cut back on alpha hydroxy acid and beta hydroxy acid products during dry winter conditions because they can irritate skin even alongside moisturizer. Avoid scented, deodorant and antibacterial soaps. If skin is raw, soft cotton or silk clothing and fragrance free laundry detergent can reduce irritation. Older skin loses water more easily, and medications or medical conditions can also contribute to dryness.24

When should you get medical help?

See a dermatologist if humidity changes and gentle skincare do not improve the problem; you do not need to wait for bleeding cracks. Very itchy circular or oval patches need assessment rather than being assumed to be ordinary dryness. Seek medical advice for heavy oozing, yellow crusts, hot or painful swelling, or feeling unwell, which can signal infection in eczema patches. Do not stop prescribed medicine without speaking to the prescriber.27