Tap water and our skin

Is tap water bad for your skin and hair? 

Interest in preventive healthcare has increased in the last couple of years and with this, people are starting to look into the impact of chlorinated and hard water on the skin and hair. How does chlorine and hard water impact the skin, what is the science behind this and what kind of water filters are proven to work?

In this blog post we tackle these questions and provide insights on how to choose the right water filter for home. For a short answer, jump straight to the conclusion.

If you are worried about bad tap water for drinking then read about why you should consider having a water filter and how they work

Why is tap water an issue for the skin?

The skin is the largest organ of the body, and it fulfils many functions including:
皮肤是人体最大的器官,它具有许多功能 包括:

  • A barrier function, to protect the body from the environment
  • A temperature regulator
  • An immune organ, to detect infections
  • A sensory organ, to detect temperature, touch, and vibration

  • 屏障功能,保护身体不受环境影响
  • 一个温度调节器
  • 一个免疫器官,用于检测感染情况
  • 一种感觉器官,用于探测温度、触觉和振动

Therefore it’s pretty natural that it’s also the most exposed to problems. Skin diseases affect around 23 to 33% of the population at any given time, and are the most common reason for people to consult their doctor when a new problem arises. Non-clinical dry and irritated skin and hair affect to even more people.

Consequently, skin and hair care is a huge industry. And big money attracts both honest and dishonest companies and individuals.

So what are the facts related to how tap water impacts the skin?

First of all, we don’t need scientific studies to show that chlorinated and hard water impacts people with sensitive skin. Compare showering in hard chlorinated water with soft less chlorinated water and most people immediately notice the difference. But are there any other proven negative effects?
比较在硬氯化水中淋浴与较少氯化的软水,大多数人会立即注意到差异。 但是还有其他已证实的负面影响吗?

Scientifically, it’s been difficult to prove causality on a larger scale, as there are so many factors that impact the skin.

Hard water

In recent studies comparing post / post/zip codes in the UK and US found that hard water can increase the risk of developing eczema – a painful skin complaint affecting one in five people. The condition causes red, itchy, inflamed, cracked and sore skin and can be exacerbated by a number of factors, including stress, chemical detergents, soaps and perfumes as well as diet and food. Dermatologists and the NHS now recognise hard water as a possible trigger for exacerbating eczema.
在最近的研究中,比较了英国和美国的邮政/邮局/邮政编码,发现硬水可以增加患湿疹的风险--一种影响五分之一人的痛苦的皮肤投诉。这种情况会导致皮肤发红、发痒、发炎、开裂和疼痛,并可能因一些因素而加剧,包括压力、化学洗涤剂、肥皂和香水以及饮食和食物。 皮肤科医生和国家医疗服务系统现在认识到硬水可能是加剧湿疹的一个诱因。

It is most common in babies, affecting at least 10% of infants at some stage. Although it often disappears in childhood, it can carry into adult life.

However, other studies such as this from UK show no or very limited impact from hard or chlorinated water: http://dwi.defra.gov.uk/research/completed-research/reports/dwi70-2-257.pdf

Overall it’s non-conclusive.

Chlorine and chlorine by-products (THMs)
氯和氯副产品 (三卤甲烷) 

An area that water scientists take very seriously is THMs (chlorine by-products). When chlorine combines with organic compounds, such as the sweat and oil on our skin, it may produce trihalomethane byproducts, commonly referred to as THMs. The levels of THMs produced when you take a hot bath or shower are rather low, however, over time, these carcinogens could have increasingly detrimental effects. Read more here.

Some research has even associated chlorine with heart defects and other medical conditions for infants. See 2002 study published in the journal Environmental Research here.

Companies and influencers promoting water filters also make the following claims, although we have not found any research or studies to back them up:

  • The skin absorbs the chlorine and other contaminants from the tap water, effectively poisoning the body
  • Chlorinated water accelerates the aging process, similar to the effects of extended exposure to the sun
  • Chlorinated water can deplete the skin of its natural oils that hold moisture in, leading to dry and itchy skin
  • Chlorine not only kills the bad bacteria that can make us sick, but it also kills good bacteria on which our our skin relies.
  • 皮肤从自来水中吸收氯和其他污染物,有效毒害身体
  • 氯化水加速了老化过程,类似于长时间暴露在阳光下的影响
  • 氯化水会使皮肤失去保持水分的天然油脂,导致皮肤干燥和瘙痒。
  • 氯不仅能杀死能使我们生病的有害细菌,而且还能杀死我们的皮肤所依赖的有益细菌。

What kind of filters protect the skin and hair from negative impacts of tap water?

This is where science is of great help, because there’s a huge gap between different types of filters. Some bluntly do nothing to improve the water while others are very effective in removing certain substances, such as chlorine.
这就是科学大有帮助的地方,因为不同类型的滤水器之间存在巨大差距。 有些直言不讳地改善水质,而另一些则非常有效地去除某些物质,例如氯。

First of all, only trust filters that have an independent lab testing or certification showing effectiveness and what they filter. In Europe and the EU, certified water lab is a great quality stamp whereas for the US, NSF is the best.

Secondly, most shower filters last 2-6 months. If they claim to last longer, then make sure that this is included in the test results.

Thirdly, there’s only one technology that has been proven to work directly in the shower and that’s KDF. KDF-55 is the most efficient filtering technology to remove chlorine and water-soluble heavy metals from high pressure hot tap water. It is to be noted that since KDF is a rather expensive patented technology, some companies mix it up with other compounds such as activated carbon. Make sure you know the proportion of the different compounds that make up a filter before purchasing.

Scientifically speaking, none of the shower filters soften the water. For people with sensitive skin removing chlorine does however provide a softening experience. However, for real water softening a whole house filter system will be required. More about this here.
从科学上讲,没有任何淋浴过滤器可以软化水。 然而,对于皮肤敏感的人来说,去除氯确实可以提供软化体验。 然而,对于真正的水软化,需要一个全屋过滤系统。 这里有更多关于这方面的信息。

Other methods such as Vitamin C and activated carbon may work as a complement but not on their own. Other substances such as e.g. magnetic or black stones have no scientific proof nor other evidence that they work.

Conclusion about unhealthy tap water

Your local tap water may cause dryness and irritation of facial skin and hair or eczema.
If this is the case, a bathroom faucet water purifier or shower filter, such as EcoPro and Showerpro, can help.
如果是这种情况,那么一个卫生间龙头净水器或淋浴过滤器,如EcoPro and Showerpro 可以提供帮助。

When choosing a water filter make sure it:

  • Has independent lab tests in Europe or NSF certification in the US
  • Uses a proven filtering technology a such as KDF
  • Provides realistic time frame for how long it lasts (typically 2-6 months)

  • 在欧洲拥有独立实验室测试或在美国获得 NSF 认证
  • 使用经过验证的过滤技术,例如 KDF
  • 提供有关持续多长时间的现实时间框架(通常为 2-6 个月)

And once you have a water filter installed, replace it as frequently as suggested or even more if you use a lot.

Hopefully, this will help you find a reliable solution for better skin and hair. Enjoy!

Additional references: US Department of Health & Human Services
其他参考资料: 美国卫生与公众服务部