The Surprising Cause of Eczema – And How You Can Fix It

Eczema is not going to kill you, but ask anyone who suffers from it, and they will be quick to tell you that it sure is aggravating.

The symptoms of eczema (also called atopic dermatitis) include inflamed, dry skin that can itch intensely and can often result in secondary skin infections. Eczema can affect any part of the body.

The other reason why it’s so aggravating is because it is frequently difficult to cure. That’s because there can be many causes. And it’s often hard to find them.

But here’s one cause that might surprise you. And how to fix it.

A new study from the University of Sheffield and King's College in London has discovered that washing with hard water damages the skin barrier. This makes the skin extra sensitive to potential irritants, including those found in everyday washing products such as soaps and shampoos. And that can cause eczema. Here’s how it works.

Hard water is water that contains high levels of calcium and magnesium. When you wash with hard water and soap, the surfactants in the soap combine with the calcium and magnesium and convert them into insoluble residues. These residues then precipitate onto the skin and ruin the pH (acid balance) of the skin. Healthy skin is acidic. However, these magnesium and calcium residues are alkaline and act to ruin the acid pH of the skin. This disturbs the skin’s natural function as a physical barrier. It also makes the skin more sensitive to anything it contacts, as well as more prone to infection.

According to the lead author of the study, Dr. Simon Danby, "By damaging the skin barrier, washing with hard water may contribute to the development of eczema – a chronic skin condition characterized by an intensely itchy red rash. Patients with eczema are much more sensitive to the effects of hard water than people with healthy skin.”

The researchers looked at 80 men and women. Some of them had eczema, and some did not. Some of the eczema patients had genetic mutations known as FLG mutations. These mutations are associated with a genetic predisposition to a skin barrier defect. Up to half of all people with eczema carry the mutations. The skin of each participant was washed with a common soap and shampoo surfactant known as sodium lauryl sulfate in water of varying degrees of hardness. The skin was then completely rinsed and covered with chambers to determine the effects of the residues. Here’s what they found.

No matter how well the participants rinsed their skin, the areas washed with hard water exhibited significantly increased residues. The residues dehydrated the skin and caused irritation. This was much more pronounced in the skin of the eczema patients, particularly in those with the FLG mutations. When the researchers substituted soft water (water with the magnesium and calcium removed), they did not see any residues. They were clearly due to the hard water. The researchers concluded, “Barrier impairment resulting from the interaction between hard water and surfactants is a contributory factor to the development of eczema.” And they had more to say about children with eczema.

According to the authors, “Installation of a water softener in early life may be able to prevent eczema development.” One in five children and one in 12 adults in the United Kingdom suffer from eczema, costing the National Health Service well over 500 million pounds every year. Author Dr. Carsten Flohr said, “It is during the first few days and months of life that our skin is most susceptible to damage and most at risk of developing eczema. For that reason, we are now embarking on a pilot trial to investigate whether installing a domestic water softener around birth can prevent skin barrier breakdown and eczema in those living in hard water areas.”

Do you have hard water or not? Signs of hard water include spots on dishes and glasses after washing and film on shower walls and tubs. Here’s a simple way to test whether or not your water is hard. Fill a clear glass jar with water and add 10 drops of liquid soap. Shake the bottle and look for suds. Gradually shake in more soap and set the bottle down. If the soapy solution foams up quickly, creating a lot of suds, and the water below the suds layer is relatively clear, and there’s no residue on the bottle when you pour the water out, you probably have at least fairly soft water. Also, some water companies will test your water for hardness.

If you have hard water and eczema that you can’t seem to get rid of, you might want to get a water softener for your house.

Yours for better health,

Frank Shallenberger, MD