Hard Water and What it Does to Your Hair

Hard Water and What it Does to Your Hair

Do you have hard water or soft water? The scale of hard to soft refers to the concentration of minerals in the water. The more calcium and magnesium (or iron, copper, lime, sodium, and so on) the water has, the “harder” it is.

You can’t actually see these minerals, but it’s pretty likely that you have hard water at home. In fact, if you check out a hard water map, you’ll see that about 85% of the U.S. does.

Hard water in the shower

What Does Hard Water Do to Hair?

Hard water minerals bond to hair in the same way that conditioner does. The more damaged the hair (heat, highlighting, permanent color, relaxer, permanent wave, brushing, sunlight, mechanical damage), the more minerals will bond to it.

Hard water minerals can create stiffness, inflexibility, brittleness and breakage, dullness and friction in hair. For low-porosity hair, hard water can exacerbate the low porosity behavior and make hair even more intolerant of conditioners and oils. Even low-porosity hair can have chipped cuticle edges where minerals can bond.

What does "hard water" feel like or look like?

Hard water build up tends to make hair feel dry, rough, stiff or less soft (more rigid). It may cause hair to look dull and frizzy. Some hair may get a brassy or reddish discoloration or grayish. If there is a substantial amount of iron in your water, orange shades tend to appear, especially in lighter-colored hair. Some people's hair will not grow past a certain length (i.e. shoulder-length) when their water is very hard because hair may become brittle with hard water accumulation.

water softness test


How to Know If You Have Hard Water

When hard water evaporates, it leaves the minerals behind. If you’ve ever seen water droplet residue on a glass after you take it out of the dishwasher, you’re looking at a mineral deposit from your water. If you’re constantly battling a powdery white or greenish coating on and around your faucets—that’s a good sign that you have hard water.


The most efficient way to detect hard water is to purchase a small hard water testing kit. Trichologist David Adams recommends the Life2O Water Hardness Test Strips ($10 for 100), but there are tons of equally effective options. They’re generally affordable and easy to use—just dip a test strip in a cup of water, wait a minute, and then compare your results to a color chart.

How to Combat Hard Water

Where you live doesn't need to ruin your hair. There are a few steps to not only lessen hard water damage, but repair it.


1. Install a showerhead water filter

The filtration system removes excess minerals. Showerhead filters vary in price and can start at $100 but could be less expensive than loading up on clarifying products.

FEELSO Shower Filter

shower head



2. Use a Chelating or Clarifying Shampoo

To remove mineral build-up from your hair, you need a shampoo which can pull minerals away from their bond with your hair - a chelating shampoo. Most will be labeled as "hard water shampoo" or hard water treatment, or as chelating or purifying shampoos.

OUAI Detox Shampoo

ouai shampoo



3. Try an apple cider vinegar rinse

Apple cider vinegar is a great example and a popular ingredient for DIY treatments, since most of us have it in our pantries. If you’re going the home-remedy route, mix five parts water to one part vinegar in a spray bottle, spray your scalp and work the formula into your ends, let it sit for five minutes, then rinse.

BRAGO Apple Cider Vinegar

apple cider vinegar

4. Finish with Argan oil

Apply pure Argan oil to dump hair to restore moisture. Focus on the ends and avoid the roots to prevent hair from looking greasy.


argan oil






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