Hard water is a common issue in many households across the world. Hard water is water that has a high mineral content, usually calcium and magnesium. The minerals in hard water can cause problems for homeowners, as it can lead to clogged pipes, soap scum buildup, and even damage to household appliances. Hard water has also gained notorious recognition for its negative ramifications on hair.
Is Hard Water Bad for Hair?
To understand the impact hard water can have on hair, it's important first to learn what makes water "hard." The hardness of water is determined by the amount of calcium carbonate and magnesium sulfate found in the water.1
Hardness in water is often believed to cause dry, brittle hair amongst its users and has also been implicated in preventing soap from lathering properly. It's also important to note that there are two types of hardness: temporary and permanent. Temporary hardness salts (bicarbonate salts) can be removed by boiling the water before use, but permanent hardness salts (sulfate salts) cannot be removed by boiling.
So how does hard water affect hair? Washing hair with hard water leads to the deposition of excessive minerals on the scalp and hair strands. This build-up of mineral content, which is primarily magnesium and calcium, can have several adverse outcomes for the appearance and health of your hair, including:
Blocks moisture: he build-up of minerals like magnesium and calcium caused by using hard water can block moisture absorption. Over time, this blocking of moisture can profoundly affect the health and appearance of the hair, as moisture is essential to elasticity and shine.
Prevents effective cleansing: The minerals found in hard water can make it difficult to form a lather which can then prevent effective cleansing of hair and scalp.This is likely the cause of the "filmy" feeling of hard water users report after washing their hair. Research shows that cleansing with hard water makes bar cleansers ineffective as it promotes soap scum that is difficult to rinse from the hair and scalp.2
Weighs the hair down: Many hard water users report their hair feeling weighed down, it can result from the mineral deposits left behind. This is likely compounded by the previously mentioned cleansing issues with hard water, as repeated poor cleansings would result in a build-up of oil and minerals.
Causes frizz and dullness: Blocking moisture and weighing the hair down can cause hair to appear dry, dull, frizzy, and unmanageable over time.
Promotes split ends and breakage: Minerals deposited on hair strands block moisture absorption and lead to dryness, which can eventually lead to breakage of hair strands. Dry hair strands are more prone to breakage, including split ends.
Makes the scalp itchy: The combination of dryness and poor cleansing caused by hard water can lead to serious scratching of your scalp. Hard water mineral deposition on the scalp can also cause a dry, itchy scalp. They can even irritate the scalp and cause itching and flaking.
Interferes with hair color: If you color your hair, you want to do everything possible to make that color last between salon visits. Hard water can also impact color-treated hair, interfering with hair color and causing the color to fade quicker.
Can Hard Water Lead to Hair Loss?
With all the potential for issues when using hard water, it's easy to see why fears about it causing hair loss would arise. Despite the laundry list of complaints caused by hard water, neither expert cited it as a direct cause of hair loss. While it may contribute to issues that increase the likelihood of hair loss, no direct link has been found.
While some people may notice changes in their hair when exposed to hard water, it is not a clear cause of hair loss. In one study, the hardness of water was not found to interfere with the tensile strength or elasticity of the hair. That said, because hard water may make it harder for moisture to penetrate the hair, hard water may leave it more susceptible to dryness and breakage.
What to Do About Hard Water
Understanding the potential risks of washing your hair with hard water, some may want to seek a solution for their hair or even their overall shower, as hard water can also affect the skin. You can take several approaches to combat hard water, including upgrading your cleansing products and investing in a specialized shower head.