What is the healthiest water filter?

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"What is the healthiest water filter?" is one of the questions Google itself shows as soon as you search for water filters, and it is also precisely the question where the answers diverge the most. One provider claims you should remove everything from your water, the other warns that filtering is actually unhealthy. Both statements are too simplistic.

What is true: Dutch tap water is excellent. According to Vewin, drinking water is more strictly controlled than food products and meets standards in 99.9 percent of measurements. In the Netherlands, therefore, you don't choose a filter out of fear, but for three reasons: taste, extra certainty about substances that just meet or just miss the standard, and convenience. In this article, we list which properties truly make a filter healthier, which filter types meet these, and what you should pay attention to before buying.

1. What makes a water filter "healthy"?

These three conditions are not a marketing trick; each excludes a known problem. The first condition excludes filters that only tackle chlorine and taste but do nothing about lead or PFAS. The second excludes systems that strip the water so much that hardly any minerals remain. The third excludes the most underestimated problem: a filter that remains in use for months too long performs less effectively and can promote bacterial growth.

Note the phrase "according to a recognized standard." A claim like "removes 99 percent" means nothing without the corresponding standard and the tested substance. More on this later, because this is precisely where most comparisons fall short.

2. Why filtering out more is not automatically healthier

There is a persistent idea that the best filter is the one that removes the most. This idea clashes with what is known about minerals in drinking water. The World Health Organization published an expert report in 2009 on calcium and magnesium in drinking water, with the core conclusion that both minerals are essential for health and that mineral-rich drinking water makes a substantial contribution to the total daily intake in some population groups. Water is therefore not just a means of quenching thirst; it also provides a part of your minerals.

This is where the criticism from drinking water experts you find online comes from: by removing minerals, you certainly don't make drinking water healthier. This criticism is justified, but it doesn't apply to all filters. It applies to filters that remove minerals without returning them, and that is mainly reverse osmosis. In our article on whether osmosis water is healthy or unhealthy, we extensively discuss what exactly disappears and when that does or does not matter.

Water companies themselves are also critical. Waternet states that a filter for the basic quality of Amsterdam tap water is not necessary and points out that very pure water can be aggressive towards pipe materials. This is a real point and it underlines the conclusion: the healthiest filter is not the most drastic filter, but the most targeted filter. Remove what doesn't belong, keep or return what does. How much calcium and magnesium is in your water depends heavily on your region; in our explanation of minerals in drinking water, you will find what each substance does.

3. What is still in Dutch tap water?

To determine what a filter should be able to do, you need to know what you are filtering against. Dutch tap water meets legal standards, but there are three groups of substances that are subject to debate.

PFAS

According to the RIVM, drinking water may legally contain a maximum of 100 nanograms of PFAS per liter, but based on new insights into immune system effects, the institute advises a stricter guideline value of 4.4 nanograms per liter, expressed as PFOA equivalents. Drinking water from groundwater usually meets this stricter value, while drinking water from surface water often does not. Approximately 60 percent of our drinking water comes from groundwater, so where you live makes a difference. Which techniques demonstrably reduce PFAS, we explain on our page about a water filter against PFAS.

Medicinal residues

The RIVM reports that medicinal residues are largely removed during drinking water preparation, but sometimes minimal amounts of residues or degradation products are found in drinking water, in concentrations well below levels where a health effect is expected. Here too, they are more often found in drinking water from surface water than in drinking water from groundwater.

Lead from your own pipes

This is the group of substances that the water company cannot solve for you, because it only enters the water after the water meter. Homes built before 1960 may still have lead pipes, and brass taps and copper couplings also release metals. This is also why the filter standard has become stricter here: NSF International lowered the maximum permissible lead concentration in filtered water to 5 micrograms per liter, a halving of the previous 10 micrograms per liter. If you want to know more about this, we go into it deeper in our article on filtering lead in tap water.

What is striking when you compare these three: these are precisely the substances for which a tap filter adds something. Bacteria and turbidity are not an issue in the Netherlands, because the water company already does that work. A filter mainly built for microbiology therefore solves a problem here that you don't have.

4. Comparing filter types for health

Filter jug with carbon cartridge

The most well-known category, with the Brita mypure P1 around 143.71 euros as an example from Dutch Google Shopping results. A carbon cartridge in a jug tackles chlorine, taste, and odor, and sometimes some heavy metals. This category is weak on health claims: the contact time is short, the cartridge is often replaced too late, and the water stands at room temperature in a jug. How this plays out in practice is detailed in our Brita water filter review.

Filter jug with ion exchanger

ZeroWater is the best-known example here and uses a five-stage cartridge that brings the TDS value to almost zero. Sounds impressive, but TDS measures all dissolved substances, including calcium and magnesium. A TDS of zero therefore also means: no more minerals. What that means for taste and costs is in our ZeroWater review for the Netherlands.

Gravity filter with ceramic element

The stainless steel canisters from Berkey, British Berkefeld, and Doulton, with target prices ranging from 380.00 to 409.00 euros for the complete systems. Strong on particles, bacteria, and cysts, and thus ideal for rainwater, well water, a boat, or an emergency kit. Minerals are retained but not supplemented, and the Doulton element must be replaced every 6 months. Our Doulton water filter review details the complete calculation.

Reverse osmosis

Technically the most drastic system, with target prices starting from approximately 449.00 euros for a compact under-sink setup. Osmosis removes a very wide range of substances, including minerals, and consumes wastewater. For those looking for a health solution, this is an ambiguous answer: very pure, but low in minerals. Some systems add a mineralization step afterward, and this specific detail determines whether the answer to this question turns out favorably.

Multi-stage under-sink filter with mineralization

A fixed system on the cold water line, out of sight, providing water from your existing tap. The PureFilter Mineral+ filters over 100 contaminants in 5 stages, including PFAS, microplastics, heavy metals, fluoride, nitrate, medicinal residues, and chlorine, and then adds magnesium, calcium, and potassium via Swedish Mineral Rock™. One cartridge lasts up to 12 months, and installation takes 5 to 10 minutes without a plumber. More about placement and variations can be found in our comparison of the best under-sink water filters.

5. Certification: the only hard evidence

This is the step that makes the difference between a health claim and a health promise. According to NSF International, NSF/ANSI 42 covers aesthetic aspects such as chlorine, taste, odor, and particles, while NSF/ANSI 53 concerns health effects and has over 50 separate reduction claims, including lead, chromium, VOCs, and Cryptosporidium. NSF/ANSI 401 also covers emerging substances such as medicinal residues and pesticides.

Additionally, there are standards for the filter itself. NSF/ANSI 61 evaluates whether materials that come into contact with drinking water release any undesirable substances, and NSF/ANSI 372 examines the lead content of the components. After all, a filter that removes lead from your water but itself releases lead is no gain.

At PureFilter, we see that customers often stumble here. They compare percentages between two product pages, while those percentages are based on different substances and different testing methods. Those who compare by standard and substance instead of by percentage often end up with a very different shortlist. In our discussion of the water filter test by the Consumentenbond, we show how test panels do or do not make this distinction.

6. Comparison table: which filter type is the healthiest?

The indicative prices below are the asking prices we found in the Dutch Google Shopping results for "healthiest water filter" on August 7, 2026. They vary by seller and promotion, so use them as a guide.

If you compare the three conditions from chapter 1 with this table, the answer divides into two scenarios. If you simply filter Dutch tap water in a kitchen, a multi-stage under-sink system with mineralization comes closest to "healthiest". If you filter rainwater, well water, or water when traveling, a ceramic gravity filter wins, simply because microbiology is the problem there.

7. When a filter becomes less healthy

• Replaced too late: a saturated carbon cartridge no longer retains anything and forms a warm, humid environment. This is the main reason why a filter jug performs worse in practice than on paper.
• Stagnant water in the jug: a jug on the counter stands at room temperature, sometimes for days. A fixed system continuously delivers freshly filtered water from the tap.
• Filtering on the hot water tap: hot tap water has been in the boiler and pipes longer and is not intended for drinking. Why that matters is explained in our article about drinking hot tap water. Always connect a filter to the cold water pipe.
• Stripping everything away without giving back: demineralized water tastes flat and no longer provides calcium and magnesium. See chapter 2.
• Claims without standards: "removes 99.99 percent" without specifying the substance and test standard is not proof. See chapter 5.

None of these points is a reason not to filter. They are, however, a reason to choose a filter whose maintenance doesn't depend on your discipline. One cartridge per year instead of ten per year is therefore also a health argument, not just a convenience argument.

8. What is the healthiest way to drink tap water?

This is also a question that Google commonly shows, and the answer is simpler than the filter discussion. Run cold water, let the tap run for a moment if it hasn't been used for a while, drink it from a clean glass or a bottle you regularly wash, and filter if you want extra assurance about substances like PFAS or lead, or if you want to improve the taste.

Bottled water is not a healthier route, but it is a more expensive and environmentally burdensome one. According to Milieu Centraal, one glass of bottled water has approximately the climate impact of 70 glasses of tap water. The cost difference is just as significant: a replacement filter of 49.90 euros per year amounts to about 0.14 euros per day, compared to 1 to 2 euros per day for bottled water. If you want to see the full consideration, you can find it in our comparison of tap water and bottled water.

9. Buying advice: which filter suits your situation?

• You want pure and mineral-rich water from your regular tap every day: choose a multi-stage under-sink system with a mineralization step. No refilling, nothing on the countertop.
• You live in a house built before 1960: pay specific attention to an NSF 53 claim for lead and NSF 372 for the filter components themselves.
• You live in an area with drinking water from surface water: then the PFAS claim weighs more heavily. Check if it has been explicitly tested.
• You filter rainwater, well water, or water when traveling: a ceramic gravity filter is appropriate here, as microbiology is the real risk.
• You want the lowest annual costs: calculate with the number of cartridges per year, not the purchase price. Ten cartridges at 8 euros are more expensive than one at 49.90 euros.

If you're still undecided between types and brands, our comparison of the best water filter will help you further, and how a water filter works explains the technology step by step. If you want to immediately see what's in stock, check out the home water filter or go directly to buy a water filter.

10. Frequently Asked Questions

11. Conclusion

The healthiest water filter is not the filter that removes the most, but the filter that removes the right things and leaves the rest. Three conditions determine this: demonstrable reduction according to a recognized standard, minerals that are retained or supplemented, and maintenance that you can realistically sustain. Anyone who compares based on these three points will see the market differently: percentages on product pages say less than the standard under which they were tested.

For Dutch tap water, a multi-stage under-sink system with mineralization comes closest to this ideal. The PureFilter Mineral+ filters over 100 contaminants in 5 steps, is certified according to NSF 42, 53, 61, and 372, adds magnesium, calcium, and potassium via Swedish Mineral Rock™, and uses one cartridge per year costing 49.90 euros, approximately 0.14 euros per day. Installation takes 5 to 10 minutes, without a plumber.

If you wish to compare further, we present the options side-by-side on our page about the best water filter, and practical questions about installation and warranty are in our frequently asked questions.