10 Myths and Facts about your Shower Water

What are the commont myths and facts about shower water? 

Just like with drinking water filters there are a lot of companies and “health experts” that spread unscientific or even false information for their own benefits. Blogs and the Amazon marketplace are filled with false myths about showering water and water filtration benefits. Therefore we’ve tried to capture the most common myths about shower water related issues to your skin, hair and health.

1. The skin absorbs chlorine when showering

Mostly false.

Some blogs and websites claim that a 10-minute shower causes your body to absorb the equivalence of 8 to glasses of chlorinated drinking water.

The health risks caused by chlorine absorption are explained as follows in a paper by The Department of Community Health in Michigan:

“The skin does not absorb chlorine well, but small amounts can pass through the skin when people are exposed to chlorine gas, bleach, or come into contact with water or soil containing high levels of chlorine. Although small amounts of chlorine can pass through the skin, it is eliminated from the body rapidly. Chlorine may irritate or burn the skin, especially moist areas.”

2. Chloroform (one of the THMs) which may be cancer-causing can is a by-product from showering in chlorinated hot water

True.

There is plenty of evidence and research that shows that we may inhale THMs from chlorinated tap water.

Science News reported that researchers found increases in chloroform in study participants’ lungs of about 2.7ppb after a 10-minute shower. Combined with warm water opening pores, skin absorption and lung inhalation during a 10-minute shower showed to be greater than the amount that would be ingested by drinking 8 glasses of the same water.

The EU has also recently published several studies showing that elevated levels of chlorine by-products such as THMs increase the risk of bladder cancer causing deaths per year in Europe.

Therefore we should be wary of total THMs above the maximum limit (100 ppm) in our tap water. 

References to two of the studies:
https://www.ncbi.nlm.nih.gov/pubmed/15138448
https://www.ncbi.nlm.nih.gov/pubmed/16556748

Most shower filters don’t remove THMs due to the high water pressure. However, ProShower that combines KDF 55 and activated carbon have proven to reduce THMs and VOCs based on independent tests.

3. Chlorine in shower water can lead to hair loss

False.

Normal exposure to chlorine does not cause hair loss. This myth has been debunked after a study was published in a recent issue of the journal of dermatologist . In the study, researchers compared the hair of 67 professional swimmers to that of 54 individuals who spent little to no time in the pool. Although swimmers’ hair exhibited signs of chlorine-induced damage (i.e. dryness and coarseness), swimmers were not significantly more likely to experience hair loss.

However, there is evidence that abnormally high exposure to chlorine might cause the scalp to become agitated, dry, and flaky. Thinning or shedding might occur as a result, but it’s important to understand that the chlorine exposure needed to bring about such side effects far exceeds that of a normal swimming pool.

Source: https://www.nytimes.com/2007/10/09/health/09real.html

4. Facts about water: Shower filters remove all chlorine

False.

Good filters remove 90% or more but there are filters that don’t remove chlorine at all. The ones that claim 99% removal are most likely made up results. Amazon is full of cheap Chinese and Korean shower that remove a small proportion of chlorine despite the raving reviews. Filters certified by the NSF #177 Standard (the US water filter standard) — only indicates that a filter will remove 50% of free chlorine in the water. ProShower is tested to filter over 90%. 

Make sure that the the manufacturers provide independent test results for their filters before buying.

5. KDF shower filters are the most effective at removing chlorine

True.

KDF removes “free chlorine” (chlorine that has not combined with other constituents in water) under heavy pressure with hot water. Carbon filters are virtually useless in showers, because they do not work when the water is warm, high pressure and they also get clogged fairly quickly.

The claim that Vitamin C filters remove chlorine is more complicated. We’ve tried to find independent research that shows the effectiveness without success. Vitamin C does work in the bathtub though as there is sufficient time for the water and Vitamin C to mix.

In an interview by Bloomberg Neal Langerman at the American Chemical Society Division of Chemical Health and Safety. “From a chemistry standpoint, vitamin C does react with chlorine and consume it. The concept has even been proven by the U.S. Department of Agriculture. But the filters are all hype. First off, chlorine and chloramines do not cross the skin barrier, nor does vitamin C. … [Also] I don’t think the reaction would be complete—the neutralization, if you will—by the time the water hits your head or flows down the drain.”

Source: KDF

The conclusion from our research is that Vitamin C is most like insufficient on it’s own but combined with KDF it could be.

6. Shower filters soften the water?

False.

A shower filter will not soften water in the way a traditional softener does, but it will remove chlorine and other chemical contaminants, making the water much less harsh and leaving your skin and hair feeling significantly softer. In addition to this shower filters with KDF will significantly reduce limescale formation.

7. Shower filters reduce water pressure?

False.

Most shower filters process water at 10 Liters (2.5 gallons) per minute, which is the same flow regulation as a standard shower head. However, it’s not a bad idea to combine your filter with a water saving shower head to save water consumption and money. You can find a list and review of shower heads here.

8. Shower filters last 12 months or more

False.

Based on two 10-minue showers per day normal shower filters will last a maximum of 3-6 months. Most filters significantly shorter. Always make sure that the manufacturer provides a report on the capacity. Unfortunately it’s difficult to notice the difference between fully effective and partially so better be safe than sorry and change as frequent as the manufacturer recommends.

9. Vitamins C infused shower filters are better for the skin

Probably false.

According to Patricia Farris, a doctor that specialises in dermatology Vitamin C has lots of benefits for the skin. It can be absorbed through the skin if it is formulated properly. Vitamin C can soften lines and wrinkles by boosting collagen production, lighten hyperpigmentation, and protect the skin from UV damage.”

But will it work with a shower filter?
“Most likely not. While a vitamin C-infused shower sounds good in theory, it will probably provide very little skin benefit,” says Farris. “Vitamin C must be formulated and packaged in a very careful way in order to stabilize it and prevent it from becoming oxidized [which makes it ineffective]. If it’s just sprayed out of the shower, the majority of it will be inactivated rather quickly as it is exposed to air.”

Source: Mens Health

There is no scientific evidence that Vitamin C showers benefit the skin.

10. Showering and bathing with chlorinated water could pose a risk for pregnant women and children

Maybe.

There is some evidence that CBPs affect fetal growth, and your genes may influence how much of an effect CBPs have during pregnancy. Source: Genefood

A study conducted by a team in Russia determined that women who drank or took showers in unfiltered water laced with chlorine and chloramine contamination resulted in various complications with the pregnancy, including spontaneous abortions, stillbirth, low birth weight, premature delivery, and a spectrum of birth defects ranging from nerve damage to weak hearts. Source: NIH

For children, a hot bath or shower with unfiltered municipal water could have dangerous effects on their development. In Belgium, a study was done to find out if there was any correlation between school children who spent time breathing the air in an indoor swimming pool and an increase in lung permeation and the development of asthma. Children who played frequently at the pool had an increased risk of developing juvenile asthma, and in some cases the symptoms were severe. Source: NIH

They also had more damaged epithelial tissue, which is the tissue that makes up the outer layer of skin and lines the insides of the lungs. This study confirms just how harmful chlorine vapors can be for a child’s respiratory system, not just in community pools, but at home in showers and baths, too.

Real conclusions can not be drawn from the limited studies, especially not since no studies specifically on the effects of showering in relation to pregnancy have been done. Considering the other health hazards it may be wise to be better safe than sorry though. Use a shower filter such as ShowerPro.

Did you know all of this about water in your shower before? Did we miss anything?

ShowerPro Filter by TAPP Water is available to buy on our website and Amazon in the UK, Germany, Spain, Italy and France.

Learn more about ProShower and the benefits of using a shower filter.

Also read our article on myths about limescale in tap water, common myths about drinking water and myths about bottled vs tap water.