Many of us have heard words like “hard” and “soft” water thrown around before, but few actually understand what they mean. After all, how could water feel like anything besides a plain ol’ liquid? Contrary to what they sound like, hard and soft water don’t have anything to do with how H2O feels. Hardness is actually defined by the amount of minerals in the water. In the hair world, this is relevant because different types of water can have different impacts on your mane.
To get answers to all of our questions about hard water vs. soft water, we reached out to Nikki Lee of 901 Salon in Hollywood. She explained the differences between hard vs. soft water, how each can affect your hair, and what you can do about it. And, before you swear off washing your hair forever, we’re sharing our favorite L'Oréal innovations to help protect strands. Keep scrolling for everything you need to know.
What Is Hard Water?
According to the United States Geological Survey (USGS), water is considered hard when it has a higher-than-usual concentration of minerals, primarily calcium and magnesium. Water can become hard naturally as it picks up minerals from rocks as it flows through rivers, streams, and wells.
While hard water is generally thought of as safe to drink, cook with, and bathe in, many cities task their water treatment plants with filtering out as many minerals as possible. However, filtered water can sometimes pick up more minerals as it leaves the treatment plant and makes its way to your home through hundreds of miles of metal pipes. It’s suspected that 85% of U.S. homes have water that is considered hard.
Is hard water bad for your hair?
Hard water doesn’t just sound bad for your hair—it actually can be.
“All the minerals and heavy metals in hard water can cause your hair to become dry, brittle, brassy, and dull,” Lee explains. “Your scalp can also get flaky and itchy, too.”
Salon hair color is especially vulnerable to hard water, which can strip and fade your hue more quickly. If you find yourself constantly booking touch-up sessions, hard water may be to blame. Not to mention, it can impact your future hair color, too: When your hair fibers are coated in a buildup of minerals and metals, it can cause less-than-optimal results when you dye your hair. Your resulting hue can appear dull, uneven, or lack shine.
Many brands have introduced ranges specifically designed to address hard water damage. One example is the L'Oréal Professionnel Serie Expert Metal Detox. This five-product line is formulated with patented technology and enriched with Glicoamine to neutralize metals before coloring, detox hair after a salon service, and prevent future particles from penetrating the hair fiber. In Metal Detox, you’ll find a pre-shampoo treatment, shampoo, mask, oil, and leave-in cream that can be used together or mixed and matched based on your styling needs.
Another collection made to manage the impacts of hard water is Kérastase Premiére. The powerful six-part system helps fight calcium buildup, reconnect broken links between keratin chains, and restore hair to its premier state. Learn more about the products (and see some pretty compelling results) in our complete Kérastase Première Review.
Does hard water make your hair greasy?
While hard water is typically more drying, the minerals can also mix with your natural oils and leave your mane looking greasy. These minerals may also interact with the ingredients in your shampoos and other hair products, impacting their effectiveness. If you’re dealing with oily hair from hard water, consider installing a softening filter in your shower. In the meantime, reach for a dry shampoo like Matrix Refresher Dry Shampoo to help refresh your hair, absorb excess oil, and extend the time between wash days.
How can you tell if you have hard water?
It can be tricky to tell if the stream coming from your shower is hard water vs. soft water just by looking at it. However, there are several ways to test your water to determine its hardness.
- Take a shower. If you have hard water, your soap will have a harder time creating a rich, foamy lather. This can lead to using more soap or shampoo than usual to get clean, and your skin may even still feel a bit “slimy” after.
- Examine your showerhead or faucet. Look for white, chalky deposits around faucets, showerheads, and other water fixtures. These deposits are mainly calcium and magnesium minerals left behind as the water evaporates.
- Do a taste test. Comparing the taste of hard vs. soft water is mixed. However, a general consensus is that soft water can sometimes taste slightly saltier due to the addition of potassium and sodium ions.
- Pay attention to your laundry. Clothes washed in hard water may feel stiff and rough after washing, even when using fabric softener.
- Plug in your zip code. If you suspect your home has hard water, enter your zip code here to find out.
What Is Soft Water?
Soft water is the exact opposite of hard water in that it has a low concentration of minerals. Soft water can occur for several reasons: Either the water has not flowed through any rocks or wells (i.e., rainwater), the rocks the water did flow through had a very low concentration of soluble minerals, or the minerals have been filtered out.
Does soft water make your hair softer?
Despite what its name may suggest, soft water itself can’t make your locks, well, soft. If you recently switched from hard water to soft water, you may notice that your strands feel silkier and more manageable. However, this change is likely because you’re no longer exposing your hair to the drying effects of hard water.
What are the disadvantages of soft water?
Washing your strands with soft water can sometimes be better for your hair, but it can also present some challenges, depending on your hair type.
“Soft water can actually make your hair greasy and flat,” Lee says. “The soft water will make your hair hold on to your products, which can also cause buildup.”
This can be particularly difficult for people with fine or oil-prone hair. If you have soft water in your shower, combat it by using a volumizing shampoo and conditioner duo like Pureology Pure Volume Shampoo and Conditioner.
Hard Water vs. Soft Water: Which Is Better for Your Hair:
Both hard and soft water come with their own set of hair woes, but hard water is typically seen as the more problematic of the two. In addition to arming yourself with the abovementioned decalcifying haircare products, Lee suggests investing in a shower filter. Most shower heads are easy to install and can filter several minerals and heavy metals out of your water. Boiling your shower water is another way to rid your tap water of minerals. You can also forgo tap water altogether and wash your hair with bottled water.
If installing a shower filter, boiling water, or using bottled water is more work than you’re looking to do, swap out your regular shampoo for a clarifying one like Redken’s Hair Cleansing Cream Clarifying Shampoo. This formula helps remove hard water, pollution, excess oils, and buildup while strengthening and adding shine.
Next Up: L’Oréal Professionnel Serie Metal Detox Review
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