We typically assume keeping skin clean is the first step in keeping it healthy. And generally that’s true. But if you have eczema, the very act of washing your skin could be aggravating the issue.

Don’t worry – the solution isn’t to stop bathing. But you do need to take a close look at what you’re bathing in.

Most of us assume that what comes out of the tap in our homes is plain old H2O. But it actually contains trace amounts of minerals like calcium and magnesium, which we normally recognize as benign and even helpful. But when levels of these minerals get too high, you have what water companies commonly call “hard water.” And that can be hard on your skin.

If you suffer from eczema, you’ve probably tried any number of solutions. Eczema can be notoriously tricky to pin down. Both internal and external factors can contribute. And the external factors can include pollution from the environment and various toxins in household products like laundry detergent. So you do need to keep your skin clean to avoid further irritation. But what happens when that just makes the problem worse?

Link Between Hard Water and Eczema

Researchers recognized that people who live in areas where hard water is more common tend to have higher rates of eczema. So they set out to determine if there is a link between the two.

The researchers knew that the skin’s barrier function plays an important role in eczema. If you compromise the barrier, eczema risk skyrockets. Many people with eczema have a mutation in the filaggrin gene (FLG). The mutation causes the skin barrier to function improperly. Having the FLG mutation is the biggest genetic risk factor for eczema. So the researchers made sure to take this gene into consideration. But it’s not the only factor that affects eczema risk and severity.

Toxins lurking in your products can make eczema worse. These toxins can include chemicals in personal care products. Many people are careful with products they know will sit on their skin for a long time, like lotions or serums. But if you’re just going to rinse off a product like shampoo or body wash, what’s the big deal?

The big deal, suggest the researchers, is that these products don’t “rinse off” nearly as well as our eyes tell us they do. And this may be especially true if you have hard water.

Surfactants or detergents can interact with minerals in hard water. Calcium in particular makes surfactants less soluble. That means they are a lot less likely to budge off the skin – even if you rinse them with water.

You may have heard of one common surfactant: sodium lauryl sulfate (SLS). We’ve discussed the dangers of SLS many times. It’s a known irritant and contributor to eczema. But it does make shampoos and soaps sudsy and more seemingly luxurious.

Many people think those suds just go down the drain, so what’s the harm? I hope this study will convince you that there may be quite a bit of harm indeed, especially if you’re at risk of eczema.

Proof That SLS Affects Your Skin – Even When You Rinse It Off

For their study, the researchers recruited people with and without eczema. They tested the eczema patients for the FLG mutation as well.

The researchers had the participants wash their skin with a controlled amount and type of water and soap containing SLS.

When the participants washed in hard water, quite a bit of SLS remained on their skin. In fact, the amount of deposition was nearly three times higher when they used hard water compared to softened water. And the amount of SLS left behind was consistent across the participant groups.

Next, the researchers tested whether all this SLS left behind was actually causing problems. They conducted patch testing to determine this. They found that the more SLS left behind, the greater the amount of water loss from the skin. This is a good measure of skin barrier function. Using softened water correlated with less water loss from the skin.

As expected, the participants with the FLG mutation fared the worst, as they already had compromised barrier function. But even those with healthy skin experienced the negative effects.

The researchers then moved on to evaluating the results of this loss of function. They found a correlation between skin redness and the amount of SLS left on the skin. And levels of the proinflammatory cytokine IL-1α were highest in the skin sites exposed to hard water. SLS deposits also affected the participants’ skin pH levels.

The researchers stress that their study design allows them to focus on specific factors’ effects on skin. Their results indicate that hard water can be bad news for eczema sufferers. This is particularly true if you use products with irritating surfactants.

This study focused on SLS. But other studies have found similar results: hard water can also increase skin deposits of other soap ingredients, such as alkyl carboxylates, for example.

Hard Water Makes Toxins Stick to Your Clothes

And it’s not just bathing that’s a problem. Using hard water to wash clothes can also cause surfactants to stick to clothes. This in turn leads to skin irritation when you don what you think are clean clothes.

Compounding the issue further is that many people choose products with surfactants because they like the lather or foam they produce. But these products don’t lather as well in hard water. So you end up using more of them.

These results are especially concerning if you have young children in the house. Even slight increases in skin water loss in infants can significantly increase their risk of developing eczema.

To decrease skin irritation, the researchers recommend using a water softener if you have hard water. They found this significantly reduced the amount of SLS residue left on the skin and the subsequent irritation. Discontinue use of SLS as well.

Choose natural products and those formulated for sensitive skin. And don’t just swap out your shower products. Dish soap, laundry detergent, and other cleaners can contain surfactants too. Be especially careful to avoid these toxins in your children’s products.

If you aren’t sure whether you have hard water or not, there are a few telltale signs you can look for. Remember, surfactants get deposited everywhere, not just on your skin. So if you see spots on your dishes and glass or a film in your shower, hard water could be the culprit.

You Can Conduct Your Own Experiment

Grab a glass jar and fill it with water and about 10 drops of liquid soap. Give it a good shake. Take a look inside the jar. Do you have a thick layer of suds on top with relatively clear water below? If so, pour the water out and check for residue in the jar. If there’s not much, your water is likely pretty soft.

If the water doesn’t suds up easily or the jar is coated in residue, you may have hard water. Some water companies will test your water if you’re concerned too. If the results indicate you have hard water, I think a water softener is a good investment. It might help your skin and reduce your frustration when you unload the dishwasher!

If you’ve already eliminated SLS and other surfactants and you have soft water but you’re still wrestling with eczema, you may need to try some other strategies. Some targeted drug therapies can be effective in treating eczema. I like non-steroidal options, which include an ointment called crisaborole, for both adults and children. However, while topical medications can be helpful, you can’t get rid of eczema for good without addressing the underlying cause, which is often systemic inflammation.

How to Reduce Inflammation

To reduce inflammation, start with the obvious solutions: clean up your diet and try to determine if there are any particular foods you're sensitive to. An allergist may be able to help you with this process. If you made any changes to anything you're putting in or on your body around the time the eczema cropped up – including moving to a new area with different water quality – that's a good place to start as well. And of course, clean up your products, as I mentioned above.

You can also help treat eczema from the inside out with bone broth (look for organic if you're buying it rather than making it yourself), good hydration, and supplements such as extra virgin cod liver oil or fermented cod liver oil (which are full of omega-3 fatty acids), as well as vitamins A and D. Just be sure you choose a reputable brand, such as Carlson Labs or Nordic Naturals.

People with mild eczema may be able to find relief with some topical strategies. I have had eczema patients experience healing and relief when they open up a probiotic capsule, mix the contents with coconut oil, and apply it to the affected areas. If you'd like to try this, I recommend using Advanced Probiotic Formula or a reputable probiotic.

Oatmeal baths can be helpful because oats contain beta glucans, which are soothing and healing for the skin. But once again, make sure your water is soft before you try this. Soaking in hard water will likely only make your eczema harder to get rid of.

Other topical remedies include using Manuka honey or apple cider vinegar. If you use apple cider vinegar, make sure it’s diluted with one cup of warm water to 1-2 tablespoons of vinegar. When applying, start with a small area, as it will be helpful or it could cause irritation in some. Apply and leave on for three to four hours.