Causes and Risk Factors of Eczema

A number of triggers can precipitate eczema (also called atopic dermatitis). While some people are more prone to developing this skin condition and tend to experience it repeatedly, eczema can affect anyone. 

The most common cause of eczema is direct skin contact with an irritant (something that causes inflammation of the skin), but other factors such as stress, skin abrasion, and sweating can cause it too. 

If you are prone to eczema, there are lifestyle factors—such as repeated exposure to irritants—that can make your skin inflamed, causing recurrent or prolonged episodes of eczema. 

Common Causes 

A number of factors can contribute to or exacerbate eczema. The condition of your skin can also make you more prone to developing atopic dermatitis, especially if you come into contact with an irritant. 

Risk factors that increase your chances of developing eczema include the following.

Dry skin: Your skin can be sensitive and susceptible to inflammation when it is dry. A superficial layer of moisture at the top surface of your skin helps protect it from damage. When you have less of that moisture barrier, your skin can become easily injured, resulting in inflammation and eczema. 

Abrasion: Your skin can get scraped fairly easily. Often, small abrasions do not cause bleeding or cuts. But these kinds of microscopic tears in your skin may occur due to repetitive movements on a rigid, jagged, or irregular surface. You can also experience superficial skin abrasions due to prolonged contact with rough materials, such as clothes, blankets, or furnishings. 

Sweating: While sweat is a type of fluid, your body’s sweat contains chemicals that are not as gentle as your skin’s natural moisture barrier. Normally, sweat evaporates or is wiped off. But when you sweat excessively or when sweat remains on your skin, it can become trapped moisture (for example under your armpits). This type of moisture can lead to skin irritation and eczema. 

Heat or cold: Your skin is at its optimal health when your environmental temperature is moderate. Excess cold or heat can be irritating to the surface of your skin. Either of these conditions can precipitate eczema. 

Stress: Stress alters your hormones and your immune function. These effects can trigger an inflammatory process anywhere in the body, including on the surface of your skin.

Irritants 

There are several common irritants known to worsen eczema. You can develop a small area of eczema on your skin in an area of irritant contact, or you can develop a more diffuse patchy rash that affects areas of skin that were not in direct contact with an irritant. And sometimes you may develop eczema from inhaling an irritant—even if you didn’t touch it.

Common irritants that can exacerbate eczema include:

• Metals, such as jewelry, clothing snaps, and utensils can cause redness, swelling, and itching on the skin. 
• Soaps, cosmetics, lotions, hair products, and perfumes can cause skin irritation for some people (while others can be completely unaffected). You may have an inflammatory response to certain product ingredients—and you can experience eczema in response to some products but not others.
• Cleaners used in the home or in an industrial setting can worsen eczema. These products may cause you to have a skin reaction if your skin comes into contact with them, and sometimes they can cause a reaction if you inhale the fumes. 
• Fabrics can cause a skin reaction, even if clothes or other materials include a small percentage of the type (or types) of fabric that irritates your skin. 
• Chemical products used in manufacturing or in a factory can also induce eczema. 
• Paints, wood stains, polishes or other materials commonly used in decorating may cause a skin reaction if you come into contact with them. 

Skin Reaction in Eczema

Eczema is not the same as an allergy. An allergy is an overreaction to a harmless product, but eczema involves actual skin irritation. Eczema is not a skin infection. Bacteria or other microorganisms do not cause eczema.

You can, however, develop a skin infection as a consequence of your eczema, especially if you have open cuts that allow entry of infectious organisms. 

Genetics

It is common for eczema to run in families. Atopic dermatitis is associated with mutations (genetic coding alterations) in the FLG gene. 

The FLG gene directs the production of filaggrin proteins. These proteins are important components of the epidermis, which is the most superficial layer of the skin. 

According to information from the U.S. National Library of Medicine, 20% to 30% of people with atopic dermatitis have an FLG gene mutation (compared with only 8% to 10% of the general population). There are a number of different mutations that can affect this gene, and many of them cause a defect in the structure or production of filaggrin proteins.

People who have food allergies tend to be more prone to eczema.

Lifestyle Risk Factors

Your day-to-day activity can increase your chances of developing eczema. A number of lifestyle factors can trigger a bout of eczema, sometimes within just a few hours. 

Common activities that worsen eczema include the following.

Frequent exposure to chemical irritants: You might work with irritants at work. Examples include working in a factory or in a spa when your skin could be exposed to chemicals for a prolonged period of time. Inhaling chemicals in these settings can exacerbate eczema as well.

Using hands without protecting skin: If you expose your hands to chemicals during activities such as cleaning, gardening, or painting, you can develop eczema if you don’t wear protective gloves or if you allow the material or residue to remain on your skin. 

Frequent hand washing or bathing: While washing your skin can remove irritants, excessive washing can diminish the protective moisture barrier that should be present on the surface of your epidermis. 

Not drying skin thoroughly: As with excessive hand washing, too much of a good thing can be harmful. If you leave water on your skin, excess moisture can become trapped if you put clothes over the wet areas before your skin can air dry. 

Rubbing or scratching skin: Scraping or scratching your skin can make you more prone to eczema. Wearing ill-fitting or rough shoes or wearing a shirt with a scratchy tag can cause you to develop a patch of eczema. Repeatedly using a coarse utensil or tool against your skin can exacerbate eczema as well.

A Word From Verywell

Eczema has a number of risk factors. If you are prone to this condition, you may notice that you have outbreaks when your skin is dry, cracked, or irritated. In addition, almost anyone can develop eczema if skin is not well taken care of.