Does Hard Water Impact Eczema?

Articles

By Melissa Tanoko

Published On: Aug 1, 2022

Last Updated On: Nov 4, 2024

If you have eczema, you probably already know about common triggers like scented laundry detergent, stress or dry skin. But did you know that if you’re using hard water, bathing with it could also be bad for your eczema?

In this article, we plunge deep into the facts on hard water. We’ll take a look at how it can impact eczema and what to do about it.

What is hard water?

When water has elevated levels of calcium and magnesium, it’s considered “hard.”1 These minerals occur naturally in rocks and soil and are dissolved into water as it flows through the ground.1 If you live in an area rich in these minerals, you’re likely to have hard water.

To determine whether or not water is hard, scientists usually measure the amount of calcium carbonate found in it. The results are often calculated as grains per gallon (gpg),milligrams per liter (mg/L) or parts per million (ppm). Hard water contains calcium carbonate levels of 7.5 gpg (121 mg/L) or above.1-2

Although hard water is considered safe to drink,3 the mineral deposits it leaves can cause problems for plumbing and household appliances.2

How hard water affects eczema

Hard water is tough on eczema-prone skin for several reasons.

“Hard water can bind to particles in soap, leaving a residue on the skin that’s more difficult to clear. This can cause further skin inflammation,” said Dr. Ari Zelig, an allergist and immunologist with Charleston ENT and Allergy in Charleston, South Carolina.

The chemistry of hard water is another important factor to consider. Dr. Zelig explained, “Hard water can also affect the pH of the skin, making it more prone to damage from irritants, allergens and bacteria.”

Why does pH matter? The skin of healthy adults is normally on the acidic side.4 This helps to form an effective barrier to protect the body from bacteria.4 When people have atopic dermatitis (AD), the pH of their skin is often higher, meaning it’s less acidic — often neutral or basic.4 This higher pH contributes to the damaged skin barrier often found in people with AD.4  

Hard water may also make kids more susceptible to eczema. “Studies have evaluated children with risk factors for the development of eczema, specifically those with a filaggrin gene mutation. Filaggrin is a very common gene that is associated with eczema,” said Dr. Zelig. “These studies found that children who are exposed to hard water were actually more likely to develop eczema.”

Four ways to find out if there is hard water in your area

Since hard water can be an issue for eczema, you may be wondering if it’s in the taps at home or a travel destination. Here are some ways to find out.

  1. Look for white mineral buildup on taps or other plumbing fixtures. If you use a dishwasher, you may also notice white spots on the clean dishes.2
  2. Check this water hardness map.5 Any areas shown in white or red have either hard or very hard water according to the U.S. Geological Survey.
  3. Test your water by purchasing a kit online or at a hardware store. Make sure it screens for minerals like calcium or magnesium, not chlorine or other contaminants.
  4. Contact your municipal government and ask for the water hardness levels in the local water supply.

How to minimize hard water exposure

If you do have hard water at home and you think it may be affecting your or a loved one’s eczema, you might consider purchasing a water softener. If you’re traveling, it may be more difficult to avoid hard water, though there are portable units that could work in a rental property or recreational vehicle (RV).7

“Water softeners may be helpful in that they strive to remove some of these excess calcium ions from hard water,” said Dr. Zelig.

With skincare water filters trending on TikTok, it can be easy to confuse water filters with softeners. They are not the same. In most cases, water filters eliminate impurities such as chlorine or lead from your water, but they do not usually remove minerals.6 However, some full filtration systems do both.7

Water softeners come in a variety of sizes. There are larger models for houses and smaller ones ideal for apartments.7 Most water softeners are salt-based and work by exchanging calcium and magnesium ions for sodium.7

“I would like to recommend that anyone suffering from eczema discuss what options you have to achieve clearer skin with your healthcare professional,” said Dr. Zelig.

Hear more from an expert on water quality and eczema

Watch the video below to hear Dr. Zelig break down how hard water, softeners or chlorine in water can affect your skin:

References:

  1. Hardness of water. United States Geological Survey (USGS). June 11, 2018. Accessed October 11, 2024. https://www.usgs.gov/special-topics/water-science-school/science/hardness-water
  2. Understanding and dealing with hard water. Department of Energy. Accessed October 11, 2024. https://www.energy.gov/energysaver/understanding-and-dealing-hard-water
  3. Sengupta P. Potential health impacts of hard water. Int J Prev Med. 2013;4(8):866-75. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3775162/
  4. Panther DJ, Jacob SE. The importance of acidification in atopic eczema: An underexplored avenue for treatment. J Clin Med. 2015;4(5):970-8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4470210/
  5. Map of water hardness in the United States. United States Geological Survey (USGS). 1977. Updated 2005. https://www.usgs.gov/media/images/map-water-hardness-united-states
  6. Water health series: Filtration facts. United States Environmental Protection Agency (EPA). September, 2005. Updated June 18, 2024. Accessed October 11, 2024. https://www.epa.gov/ground-water-and-drinking-water/home-drinking-water-filtration-fact-sheet
  7. Purchasing and maintaining a water softener. Department of Energy. Accessed October 11, 2024. https://www.energy.gov/energysaver/purchasing-and-maintaining-water-softener

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