Do Water Softeners Remove Fluoride? Here’s What Really Works


The short answer is- No, water softeners do not remove fluoride. Since fluoride ions are negatively charged, they are not exchanged by the water softening process and remain in water.

This is because because water softeners exchange ions that are positively charged such as Magnesium and Calcium(common indicators of hard water) with negatively charged ions(usually Sodium). This exchange process removes the unwanted positive ions from the water into a separate brine solution that is discarded later.

The other type of water softener- the salt free type- is also not useful as it doesn’t actually remove any dissolved ions in water. It simply reacts with hard water minerals- Calcium and Magnesium, to ensure they don’t adhere to surfaces, and ensures scaling doesn’t happen.

I’m assuming you’re still looking for an answer as to how fluoride can be removed from your water. While it is one of the more difficult ‘contaminants’ to remove, here are the 3 ways to filter fluoride out

  1. Reverse Osmosis
  2. Ion Exchange
  3. Distillation

Before going into each of these filtration techniques in detail, it’s important to understand what the existing level of fluoride in our water is like usually, as well as what level of consumption is safe for us.

Understanding Regulation For Fluoride Levels In Water

In the US, Fluoride has been added to public water supply since the 1950’s when it was found that it helps prevent tooth decay. In other countries where fluoridation isn’t practised, such as where I live-India, it is due to naturally high levels of fluoride in water.

According to the Centre For Disease Control & Prevention’s(CDC) toxicology guide, excess fluoride can cause:

  • Dental fluorosis– a condition that causes staining on the enamel.
  • Higher risk of fractures in the elderly, due to increased mineral density
  • Skeletal fluorosis– brittle bones and decreased tensile strength

There also are many other potential risks of excess fluoride which have been found through limited studies- such as lowered IQ in children, hypothyroidism, and diabetes risks.

The guide also sets a daily minimum risk level(MRL) for fluoride – 0.05 mg/kg. If this minimum risk level is met every single day in a person’s drinking water for more than a year, then that person would potentially be at risk for fluoride poisoning.

So, let’s take an example here. For an average person who weighs 60 kg, the MRL will be 60*0.05= 3 mg/day.

Here’s the problem with that:

As per the 2015 revision by US Dept. of Health & Human Services, the optimal level of fluoride in public water is 0.7 mg/L. They reduced their earlier recommended range of 0.7-1.2 mg/L owing to the variety of additional sources through which we receive fluorine nowadays.

However, a closer look still finds their recommendation somewhat at odds with the CDC’s.

An average person drinks 3-4 L of water everyday. That comes to 2.1-2.8 mg fluoride ingested everyday. Taking the above example of a 60 kg person, the minimum risk level for him(3mg/day) is uncomfortably close!

And this is just from a single source of fluoride. According to Fluoride Action Network, a person is exposed to fluoride from multiple sources every day, few of which are:

  • Dental products like toothpaste- According to oralanswers, most toothpastes contain 1500 mg fluoride in every litre. A normal stripe of toothpaste, as they show in commercials is about 1.5 ml. Which comes to about 2.25 mg fluoride right there. Would be better to start using a pea sized drop of toothpaste(~0.3 mg fluoride) than a stripe, if you don’t already
  • Non stick pans
  • Processed drinks and foods
  • Mechanically deboned meat
  • Pesticide laden food

According to W.H.O:

“Virtually all foodstuffs contain at least traces of fluorine. All vegetation contains some fluoride, which is absorbed from soil and water. Tea in particular can contain high fluoride concentrations, and levels in dry tea are on average 100 mg/kg”

Adding up fluoride consumption from even a few of these sources, it isn’t tough to cross the minimum risk limit set by the CDC.

How you can remove fluoride from your water

#1 Reverse Osmosis

Reverse Osmosis is the most effective water purification technology commercially available. It removes all viruses, bacteria, cysts, protozoa(basically- all water borne contaminants) as well as dissolved impurities like chlorine, chloramine, and heavy metals like fluoride. I would suggest employing RO as an undersink filter for drinking water and not a whole house filter because it wastes ~60% of water during purification. Imagine the wastage if it filtered all water in the house!

RO units are great for ensuring no contaminants remain in water though. They are easily available on Amazon, or if you want a comprehensive guide on RO, you can read more about them here.

#2 Ion Exchange Water Filters

Water Filter Pitcher:

Not all water filter pitchers remove fluoride, however, this filter pitcher on Amazon was the one of the rare ones that do. It has been tested to remove upto 90% of fluoride in water, among other heavy metals such as lead, arsenic, mercury, chromium, and copper.

As a bonus, it also removes chlorine, chloramines and VOC’s from water.

While these are tall claims, a little digging around proved them to be legitimate. My initial skepticism towards this product’s supposed 90% fluoride reduction rate was because the concentration of fluoride in the test sample wasn’t mentioned on it’s Amazon product page.

However, going through the product certifications on it’s website showed that it has passed EPA as well as W.H.O standards on fluoride removal from water. The most recent certification- for EPA method 300 consists of multilaboratory testing of the filter on water samples having fluoride concentration in the range 0.26-8.49 mg/L. The upper limit far surpasses the normal levels of fluoride in groundwater, and seeing as it removes still 89.36% fluoride in this particular test, I’m satisfied.

Last thing:

There is a bit of a maintenance aspect to this, as you’ll have to change the filter cartridges every few months(exact timeline depends on your water quality). I’d suggest you buy a cartridge along with the pitcher, because you never know how many months down the line you may need to change it. After that, once you have an idea, you can plan your replacement filter purchases accordingly.

PS: I loved the fact that they have a 30 day return policy as one as one that lets consumers send used filter cartridges back to the manufacturer for recycling. Read more about it here.

Countertop Gravity Water Filters:

In case you’re looking for a filter pitcher that carries more water, you can check out this product on Amazon, that has a 4.5 gallon or 17 L capacity. While it is definitely more expensive than the traditional water filter pitcher, it would make sense to buy it if you’re more than 2 people in the household, or don’t have the time to refill the pitcher a couple of times a day.

#3 Distillation:

Distillation essentially means boiling water and then collecting the water vapors in a separate container. By the end of this process, most of the dissolved salts, chemicals-which includes fluoride- would be left behind as they have a higher boiling point than water.

According to Fluoride Action Network, distillation will remove most, if not all of the fluoride in water.

Keep in mind though, that distillation is a long process. According to the product details of this popular countertop distiller on Amazon, it takes 5 hours to purify 1 gallon(~4 L) of water.

I’d rather get an Ion exchange filter or RO filter, if I were you.

Few Common Questions:

Do refrigerator filters remove fluoride from water?

No, they don’t. Refrigerator filters typically use Granular Activated Carbon(GAC) filters, which do not remove fluoride from water.

Can you remove fluoride from water by boiling it?

Boiling isn’t really effective as fluoride boils at a higher temperature than water. Distillation of water is more effective (see above)

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