The mineral content of hard water is beneficial to our internal health, but it can be less positive for our external health. In large quantities, those same minerals can negatively affect the skin and, most noticeably, hair.
How severely hard water affects hair will depend on the specific minerals in your water and the amount of them that is present. Fortunately, it is possible to overcome this using technology or a couple of reliable home remedies.
In this article, we will look at how hard water affects your hair and why. Then, we will explore what you can do to help your hair and reduce the damaging effects of hard water.
What is Hard Water?
Hard water is water that contains large amounts of minerals such as calcium, iron, and magnesium. When rainwater falls from the sky, it has no mineral content, also known as being “soft”. However, as it travels over or through the ground, it collects minerals. Areas that are rich in limestone, chalk, or marble will naturally have hard water.
The most common minerals in hard water are calcium and magnesium. It is easy to assume that this affects well water more than municipal water, but many urban areas also receive a significant amount of minerals in their water supplies (1).
Water that contains over 3 GPG (grains per gallon) is considered moderately hard. At 7 GPG, water is very hard (2). Hard water can be bad for your hair as it has a contrasting pH, so the two clash with each other.
You might notice a few telltale signs around your house that suggest hard water. These include:
- Limescale: This will usually form around water outlets, showerheads, and inside appliances (3).
- Reduced water flow: When there is a significant buildup of calcium and limescale in your pipes, they will be narrower and your water flow will be inhibited.
- Water spots: Your glasses might look cloudy or spotted with marks left by the minerals in the water.
- Dull laundry: Hard water doesn’t react well with detergents. This can dull your laundry in time — for example, white fabrics might turn gray.
- Stains in tub and showers: You might notice a grayish-white scale around the sides of your tub or shower. Hard water can also leave marks on shower doors and tiles.
How Hard Water Affects Hair
Soap and Shampoo
The minerals in hard water can react badly with soap and shampoo because there are too many soluble salts, which reduce lathering. This means you need to use more shampoo to achieve the same level of cleaning. Using too much shampoo can dry the hair and scalp by trapping oils, so hard water can indirectly damage your hair or even cause hair loss (4).
Hair strands are made up of tiny scales, similar to roof shingles. When we wash our hair with hard water, it causes those scales to stand up, making our hair feel tangled and brittle. This rough texture makes it more difficult to lather shampoo and rinse it out (5).
As hard water doesn’t lather well, it can be difficult to remove certain styling products such as hair spray and gel (6). This can cause a buildup on the scalp, making hair feel heavier and greasier as natural oils are trapped (7).
Hard water can also make your hair less pliable and more difficult to style. Attempting a simple blow-dry and using a round brush can take longer and might not have the results you expect because your hair is less supple.
Dyed hair will fade more quickly if it is repeatedly washed in hard water. The minerals separate the strands from the color. The strands also won’t absorb the color as effectively, making it more difficult to achieve the desired shade.
How pH Levels Affect Hair
The pH level of the water also plays a significant role in how it affects your hair. Hair naturally has a level of 4.5 to 5, so it is slightly acidic. In contrast, hard water is alkaline with a level of 8.5 or even higher in some locations (8).
Shampoo and hair products also have different pH levels. When these substances combine with water, they can negatively affect your hair, making it more difficult to dry or style (9).
What You Can Do to Help Your Hair
If you notice signs of hard water damage on your hair, there are a few ways you can lessen its impact or prevent it entirely:
1. Install a Water Softener
You can install a water softener in your home to remove minerals such as calcium and magnesium from your water. Softeners can be expensive but they are a worthwhile investment if you live in a region with very hard water (10).
Your water might not seem any different after softening it, but you should notice positive changes in your hair and skin. Soft water is also better for people affected by some skin conditions such as eczema, potentially reducing dandruff (11).
2. Showerhead Filter
If you still want to enjoy the benefits of the mineral content of your drinking water, you can install a shower head filter. These filter the water as it leaves the shower head — just make sure you choose one that removes minerals if you want to soften your water. Showerhead filters will also remove other contaminants and bacteria.
3. Limit Washes
Many people shampoo their hair daily 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 smooth. However, the combination of hard water and shampoo can dry your hair out, especially if you do it every day.
To prevent this, try to only shampoo your hair when it is necessary. Allowing the natural oils of the scalp to moisturize your hair can benefit it as sebum is its natural moisturizer. As your hair grows, sebum lubricates each strand — but this can be stripped away if you shampoo it every day, especially when combined with hard water.
If you have oily hair, consider sometimes using a good dry shampoo instead. These are powders that clean your hair without requiring water. They are a smart solution, but experts warn not to overuse them as they will dry your hair and can eventually cause hair loss (12).
4. Use a Vinegar Rinse
To help prevent hard water hair damage, you can perform a vinegar rinse to balance its pH level. To do this, you will need one teaspoon of apple cider vinegar mixed into two cups of water. Pour the mixture onto your hair and scalp after shampooing and allow it to sit for a few minutes. Then, rinse your hair.
The acidic vinegar will lower your hair’s pH, reducing the negative effects of hard water (13). This is an inexpensive, effective hard water hair treatment.