Can Tap Water Can Cause Hair Loss?

  • Medically reviewed by:
  • Written by: William Slator
  • Last updated: 05/12/2023

When you’re experiencing hair loss, it is common to question whether you are doing anything “wrong.” You may wonder if the hair products you are using or the foods you are eating are the root cause. But have you ever considered that the water you use to wash your hair may be a problem?

Tap water, and more specifically hard water, may be the cause of your hair thinning, hair breakage, and loss. This article will introduce the topic, including how water may be the cause of your hair loss woes. You will then learn how to combat the problem.

How Can Tap Water Cause Hair Loss?

To keep tap water safe, it is treated with chemicals like chlorine. While this kills bacteria and other potentially harmful microorganisms, it can be harsh on your scalp.

More than just chlorine and chloramines, your home’s tap water may also contain an overabundance of certain minerals. These are largely calcium and magnesium, though other minerals may exist depending on the area. If this is the case, you are dealing with a hard water problem.

Hard Water and Hair Loss

When it comes to hair loss related to tap water usage, the culprit is usually hard water.

What is Hard Water?

Hard water is defined as water with high levels of minerals like calcium and magnesium. As water is pumped through underground plumbing, it may come into contact with mineral deposits like limestone and chalk. The mineral particles are picked up along the way and delivered to homes via their taps.

There are various levels of water hardness. While indices may vary, the four general classifications are soft, moderately hard, hard, and very hard. The higher the mineral content, the harder the water.

In some areas, it is impossible to avoid hard water. This is due to the source of the water and the quality of the area’s plumbing system.

A map of the hard water areas in the UK
Hard water areas in the U.K.

There are some parts of the world with harder water than others. In Australia and Canada, for example, the hardness will vary by region. In England, though, the vast majority of the country has drinking water classified as hard or very hard.

How Might Hard Water Cause Hair Loss?

In many cases, the problem with hard water is initially with hair weakening and breakage. This can eventually evolve into hair thinning and loss.

When you wash your hair with hard water, a film develops on the hair. The film makes it difficult for moisture to penetrate the hair strands. This causes dry, brittle hair that is prone to breakage.

The build-up of minerals is not only on the hair strands but the scalp, too. This build-up may eventually clog the pores and make it difficult, if not impossible, for hair strands to penetrate the scalp. This results in less hair growth overall which can lead to the appearance of diffuse hair thinning.

If the above was not enough, there is also evidence to suggest that hard water may trigger skin irritation in patients prone to Atopic Dermatitis. This is due to skin barrier impairment after exposure to surfactants in wash products. If left untreated, the irritation may cause damage to the skin which can result in agitation-related hair loss.

How to Reverse the Effects of Hard Water on Your Hair

While you cannot always control where your water comes from, there are things you can do to either reduce the hard water in your home or combat its effects on your hair. Here are a few tips to consider.

Soften the Water

It is best to treat the problem at the source. This means replacing old, malfunctioning pipes or even rerouting pipelines.

Unless you have a well, you cannot control the source of your water. The good news is that there are various ways you can soften the water before or after it enters your home.

The best option is to add a filter to your home’s pipes at the location where water enters from the city plumbing system. Before doing so, you should have an examination of your plumbing done to ensure there are no mineral deposits in your own pipes. Otherwise, the filter will be for naught.

You can also add filters to the individual taps in your home. The downside to this option is a decreased flow rate, but the payoff is the significant reduction in mineral content in your water.

Use a Chelating Shampoo

If hard water is a problem and you are unable to treat it yourself, you can also use shampoos that help to negate most of the hard water’s harsh effects.

A chelating shampoo is formulated to remove minerals, metals, and other buildup from your hair and scalp. It is stronger than a clarifying shampoo which is most effective for removing product buildup.

The chelating shampoo should not be used daily as the formula is harsh. Instead, you should aim to use it no more than twice per week.

Wash Your Hair Less Often

In addition to a chelating shampoo, you should aim to reduce hair-washing frequency. This will have two benefits.

First, it reduces your hair’s contact with hard water. Second, it will allow your scalp’s oil production to balance out which will result in a healthier scalp and hair.

If you suffer from an oily scalp, you may believe it is impossible to reduce shampoo frequency. But the more you wash your hair, the drier your hair and scalp become. This results in the sebaceous glands overproducing sebum which causes oily scalp to begin with.

To break the vicious cycle, you can slowly reduce your shampoo frequency. If you wash your hair daily, for example, then transition to once every other day. After your scalp has become accustomed to the new schedule, reduce frequency again to once every two days.

The frequency with which you wash your hair will depend on many factors, including skin and hair type and daily activity. It is important to experiment with different frequencies until you find the one that works for you.

Can Drinking Tap Water Cause Hair Loss?

While the information above is focused on tap water’s external effects, it can also have harmful internal effects. This depends on the chemical composition of your home’s tap water.

As mentioned above, tap water can contain high levels of metals and elements like lead, mercury, and chlorine. When ingested in high concentrations, these can have both acute and chronic health effects.

Lead toxicity, for example, can have reproductive, respiratory, and neurological effects. Mercury poisoning can similarly cause issues with the nervous and endocrine systems, and it can also be detrimental to hair growth.

Aside from high levels of metals and chemical elements, pharmaceuticals and pesticides may also taint your home’s tap water. This will depend largely on the source of your city’s water and the age of your city’s plumbing system.

The good news is that filtration systems exist to remove the majority, if not all, of the contaminants above. These systems include Reverse Osmosis (RO) and Granulated Activated Carbon (GAC) filters.


When it comes to hair loss, some factors are outside your control. If your hair thinning and loss are caused by hard water, though, then there are many things you can do to improve the health of your hair.

For many people, hard water is a fact of life. But there are many ways to soften the water or reduce hard water’s effects on your hair and scalp. This can ultimately improve the health of your scalp so you can regrow strong, healthy hair.

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