How Hard Water Affects Hair & What You Can Do About It

Hard water may be healthy to drink, but how can it affect your hair?

Hard water may be healthy for our insides, but it’s a different story on the outside. Due to the high mineral content, hard water can have some unwanted effects on our outer beauty — particularly our hair.

How hard water affects hair depends on the minerals and how heavy the content is. Luckily, there are ways to beat this and restore your luscious locks.

What is Hard Water?

Hard water is water that’s high in minerals such as calcium, iron, and magnesium. As rainwater falls from the sky, it’s soft; however, as it seeps through the ground, it picks up minerals. Areas that are rich in limestone, chalk or marble will naturally have hard water.

The main minerals found in hard water are calcium and magnesium. Many people think this only occurs in well water, but city water can also have a significant amount of minerals (1).

Water that contains over 3 gpg (grains per gallon) is considered moderately hard. But it isn’t until 7 gpg that water is very hard (2).

You might notice a few signs around your house that indicate hard water. These include:

  • Limescale: This will usually form around faucet taps, showerheads, and within appliances (3).
  • Reduced water flow: When there’s a significant buildup of calcium and limescale, your water flow will be reduced significantly.
  • Water spots: Your glasses might look cloudy or full of watermarks due to the minerals in the water.
  • Dull laundry: Hard water doesn’t react well with detergents; this can cause your laundry to dull over time — for example, white fabrics can turn gray (4).
  • Stains in tub and showers: You might notice a grayish-white scale around the sides of your tub or shower. Hard water can also cause marks on shower doors and tiles.

How Hard Water Affects Hair

Soap and Shampoo

Hard water can have unwanted effects in different areas of your home, but it can also be bad for your hair. Due to the minerals, soap and shampoo don’t react well in hard water because there are too many soluble salts in the water, which means less lathering, which in turn makes us use more shampoo. Excessive use of shampoo can then dry the hair and scalp by trapping oils (5).

Hair Strands

Hair strands are made up of tiny scales, similar to roof shingles. When we wash our hair in hard water, it causes those scales to stand up, making our hair feel tangled and rough. This texture makes it difficult to lather shampoo and rinse it out (6).

Styling Problems

Since hard water doesn’t lather well, this can make it difficult to remove certain hair styling products such as hair spray and gel (7). This can cause a buildup on the scalp, making the hair feel heavy and greasy as it traps the natural oils (8).

Hard water can also cause your hair to be difficult to style and less pliable. Doing a simple blow-dry using a round brush can take longer and often ends with an unsatisfactory result because hair is less supple.

Color-treated hair will fade more quickly when continuously washed in hard water. The minerals strip the strands from the color. The standing strands also won’t absorb the color as well, making it tricky to achieve the desired shade (9).

How pH Levels Affect Hair

The pH level of the water also plays a significant role in how the hair is affected. Hair has a level of 4.5 to 5, so it’s slightly acidic. Hard water, on the other hand, is alkaline with a level of 8.5 — some areas are even higher (10).

Additionally, shampoo and different hair products also have certain pH levels. When combined with water, these can also affect your hair, making it harder to style or dry (11).

Avoid Damage

As the hair’s pH level rises, the fibers swell, causing substantial structural damage to the hair.

What You Can Do to Help Your Hair

If hard water is getting you down, these next points might give you some relief:

1. Install a Water Softener

A water softener can be installed in your home to remove minerals such as calcium and magnesium. They can be expensive, but may be worth it in areas with significantly harder water (12).

Your water might not feel any different after softening it, but you should see changes in water flow, hair, and skin (13). Soft water is also better for people dealing with certain skin conditions such as eczema (14).

2. Showerhead Filter

If you still want to benefit from the extra minerals in your drinking water, you can install a showerhead filter. These will filter the water as it exits the faucet — make sure you choose one that will remove minerals. Showerhead filters will also remove other contaminants and bacteria.

3. Limit Washes

Many of us are used to shampooing our hair every day, but this can be a mistake with hard water. Shampoos are designed to remove dirt, oil, and grease from the hair, leaving it clean and silky. But, don’t forget that hard water together with everyday shampooing can cause your hair to become even drier.

To combat this, try to limit yourself and only shampoo your hair when it’s essential. Allowing the natural oils of the scalp to moisturize your hair can benefit greatly, since sebum is the scalp’s own natural moisturizer. As the hair grows, sebum lubricates each strand — but you strip hair of healthy oil and moisture if you wash every day.

If you have oily hair, you can choose a good dry shampoo instead. These are powders that clean your hair without the need for water. It’s a smart solution, but experts warn not to overuse it as it will dry your hair and can cause hair loss (15).

4. Do a Vinegar Rinse

To help balance the pH level of your hair, you can do a vinegar rinse. For this, you’ll need one teaspoon of apple cider vinegar in two cups of water. Pour the mixture on the hair and scalp after shampooing and allow it to sit for a few minutes before rinsing through your hair after a wash.

The acidic vinegar will lower your hair’s pH and improve the health of your scalp (16).

Controlling the Frizz

How hard water affects hair depends on the hardness and pH level. Just as minerals can cause buildup in your faucet, they can cause buildup on your hair. This makes the scales of the strands stand up, changing the texture.

To help your hair overcome the frizz, you can install a water softener. However, shampooing your hair less frequently can also help. Try a good dry shampoo a couple of times a week, and you might see a big difference.

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About the Author

Sylvia Jones

Sylvia Jones is a hands-on, DIY aficionado from Indiana. She is passionate about home improvement, gardening, and environmental conservation. In her spare time, you can find Sylvia getting involved in home improvement projects around the house with her husband, or spending quality time out in the yard.