If you’re making an active effort to drink more water, you probably know how important H2O is for health.
What could be more simple? The Earth is 72% water. We need water to survive – we need more water to thrive!
And the best water is…
Well actually, that might be where it gets complicated…
Because once you dig a little deeper, there are several types of water to choose from.
You can shell out for spring water, drink purified water from the tap, filter it further yourself, or search for distilled water.
So, which is best? Let’s look into it.
What Is Purified Water?
Purified water is any water that has been filtered or otherwise treated for contaminants like:
- Chemical contaminants
- Heavy metals
Tap water worldwide is treated to remove these impurities, with different regulations for safe drinking water from country to country. In the USA, regulations are set by the EPA.
1. Coagulation and flocculation
In this first step, chemicals with a positive charge are added to water. They then bind with negatively charged particles in order to filter those chemicals out. The larger particles this produces is referred to as ‘floc’.
As it’s bigger and heavier than most components of water, floc sinks to the bottom of the water supply. This makes it easy to separate from the clean water.
The clean water (which is now at the top of the supply) is then processed through a series of filters. Filter media includes gravel, charcoal and sand. This gets rid of things like dust, bacteria, chemicals and viruses.
The final step for purifying water on a mass scale is adding chemical disinfectants like chlorine to the water supply. This should kill any remaining bacteria or viruses that have survived the rest of the process. The level of chlorine added is generally seen as safe for human consumption, though as we will see some people prefer to remove chlorine from their drinking water entirely.
Through processes somewhat like these, most tap water in the economically developed world is safe for drinking. Of course, in some countries that is not the case and bottled water is the norm. Additionally, some people who have access to technically safe tap water also want the added reassurance of home filtration systems.
The Benefits of Purified Water
Without some purification before it reaches us, we wouldn’t be able to safely drink water from the tap.
In countries with unsafe tap water, purification (or distillation) is essential before you drink water. The same is true if you’re drinking water from a natural source, unless it’s spring water.
Although the EPA sets safe upper safety limits for contaminants in drinking water that must be adhered to, the Safe Drinking Water Act allows states some wiggle room. The EPA upper limits must not be exceeded by any state, but some states have even more stringent rules about contaminants in drinking water. That means that, state to state, drinking water safety standards (and tap water quality) vary.
The Benefits of at-home Purification
Usually, additional purification means an at-home filter system.
These come in several varieties, ranging from a simple pitcher filter that improves the smell and taste of your water, to point of entry systems that purify all water coming into the home and remove heavy metals, chlorine and viruses.
These are sensible in many cases, as both heavy metals and viruses can be introduced to the water supply once it has left a treatment center, something that has been studied in relation to Flint, Michigan. Chlorine, though it does have its benefits for water treatment, has also been linked to some cancers. (3, 4)
Good at-home filter systems should adhere to NSF standards. The NSF has a whole host of standards for filters that remove various contaminants, so if you’re buying an at-home filter do look carefully at the exact standard it has achieved.
The Negatives of Purified Water
If you’re purifying water at home with filters, you will run up against a few negatives.
Firstly, many filters remove fluoride which is a much-debated topic among. Studies such as this one show that fluoride is beneficial, reducing tooth decay and dental issues in all age groups. This is why, in many countries, fluoride is added to the water supply.
Counter research, however, such as this study out of Iran, has long argued that the negative effects of fluoride overdose (nerve damage, toxicity, cognitive impairment) outweigh the positive dental outcomes.
Over time, the research has borne out that small amounts of fluoride in the water are a good thing. This is summarised in this review of the literature on the subject.
As research is still ongoing, however, some people prefer to remove the fluoride from their water. This may have negative outcomes for their teeth.
Beyond that, some filters and water treatments (most notably RO filters, and water softeners) remove beneficial minerals from water. Magnesium and calcium are both needed for our bodies to function, and getting them in our water is a net positive. They can be added back into water, but not always in as digestible a form as they usually occur.
Thinking about factors other than health, filtering or treating your water to purify it at home can be expensive and/or time consuming. Depending on the type of filter you use, the initial cost can be anything from minimal to a real investment. You also need to replace the cartridges in most filters regularly.
Finally, disposing of used filters and (with some systems) flushing waste water both have environmental impacts. It’s certainly not cut and dried that purifying water at home is the best choice for you, your family and the planet, unless of course you know for sure that your water supply is contaminated (and have a filter that can deal with those contaminants).
What Is Distilled Water?
Technically, distillation is a kind of purification.
Distilled water is processed through boiling. Water is boiled and steam-condensed. When the steam is collected, all solid contaminants are left behind, leaving only pure water.
Water that has been purified through a distillation process like this is more pure than water purified by any other method, including ion exchange, carbon filter or even reverse osmosis filter.
As outlined by Purdue, distillation at home can be effective in removing viruses, bacteria, protozoa such as giardia and heavy metals and chemicals like lead, iron and sulfate.
Distilling Water Yourself
Distilling water at home is easy. You simply have to boil water, and direct the steam to drip into a second, clean vessel. The resulting water will be distilled, and therefore free of almost all impurities.
You can also purchase or build distillation units of stills to help distill water. They heat water and direct the steam to cool in a secondary area, where it becomes distilled water.
The Benefits of Distilled Water
Distillation is the best way to deal with purifying water in some emergency situations. If you don’t have a safe and effective filter with you, distilling water is the simplest way to make sure the water you are consuming is safe.
If you have access to other safe to drink water, there are usually no additional benefits to drinking distilled water. Some studies, however, such as this one in Clinical Infectious Diseases show that some people living with immuno-suppressing illnesses like HIV or some cancers could benefit from drinking distilled water.
This kind of water also has a few non-consumption uses. The lack of dissolved minerals and chemicals in distilled water mean it’s softer on appliances and engines, for example. It is often used in:
- Electric steam irons
- Aquariums (mineral supplements should be added to the fish food)
- Car cooling systems
- Lab experiments
- Some medical devices
The Negatives of Distilled Water
The problem with the distillation process is that it’s a bit too effective.
As well as removing potentially harmful chemicals, heavy metals and other contaminants, distillation also gets rid of minerals and electrolytes we need in our diets in order to stay healthy. Distillation removes over 99% of minerals found in tap water, according to University of Georgia.
What Is Spring Water?
Not all bottled water is spring water. Some bottled water may even be tap water that has later been bottled. But, according to FDA guidelines, spring water must be water that comes naturally to the surface after flowing through underground formations like rivers or tunnels of rock.
To fulfill FDA requirement, the water needs to be collected from the spring’s mouth where it emerges, or through a borehole into the underground it moves through.
It is also important for labelling and categorising purposes the bottled water has the same composition as water collected at the spring’s mouth. If the composition is changed, it cannot be called spring water. This rules out some extraction methods, and means that collecting spring water is high effort and often either low yield or high cost. That means it’s also often expensive to buy.
Spring water is sometimes confused with mineral water. While they are similar, and technically mineral water is usually a type of spring water, they are different in the eyes of the FDA.
Mineral water comes from an underground water source just like spring water does, but it is richer in minerals. In fact, it must contain at least 250 parts per million dissolved solids. Although dissolved solids can include many substances, in mineral water they are minerals like calcium, magnesium and potassium.
For water to legally be labelled mineral water, the minerals must come from the water’s source. They cannot be added later
The Benefits of Spring Water
Spring water is essentially naturally filtered water. The rocks it travels through perform a filtration process, and beneath the Earth it comes in contact with few man made contaminants. Spring waters have long been thought of as health-giving, and research is beginning to be done into the topic in a systematic manner.
When there is no access to properly sanitized and treated municipal water, a study conducted in India showed that spring water is generally safe to drink straight from the source. Contamination may happen after it has left the spring-mouth, but is unlikely underground.
Of course, in the US, UK and other economically developed nations bottled spring water is regulated and tested for potential contaminants.
The Negatives of Spring Water
A 2017 review concluded that mineral waters in particular offer a variety of potential health benefits, but that leaching from plastic bottles (which mineral and spring waters are often stored and sold in) could have a negative impact.
We have known for some time that BPA leaches from plastic bottles into liquids stored in them, and then into our systems. The use of BPA in plastic bottles is on the decline, but it can still be found in some cheaper single-use plastics.
Glass bottles are another option, but they are obviously more expensive than plastic. In fact, buying spring water tends to be a high-cost way to get water, and it also creates a lot of waste as you will have to dispose of bottles whether they are glass or plastic.
For these reasons, very few people drink mostly or solely spring water. Unless, of course, they happen to have a spring at the bottom of their garden!
So, Which Type of Water is Best?
While it is true that, arguably, spring water is ‘best’ because it is both natural and often rich in minerals while also being free of contaminants, it is also deeply impractical for most people. Both the prohibitive cost of spring water and the environmental impact of getting rid of the bottles it comes in mean it is usually ruled out as a main source of drinking water.
Distilled water, as discussed, may be the best choice for people with a few specific immuno-compromising conditions. It’s also useful to know how to distill water for potential emergency situations. However, the lack of electrolytes and minerals in distilled water make it a poor choice for day-to-day consumption if you have access to other safe water.
Which leaves us with purified water!
Although this a broad category, generally speaking purified water makes the most sense as daily drinking and cooking water for the majority of people.
Remember, our tap water is already purified in the USA. But you can purify water further by filtering it.
How to Purify Water at Home
The EPA divides at-home water filters into two categories. These are point of entry (POE) and point of use (POU) systems.
Point of entry filter systems attach to your mains water supply, filtering all the water that enters your property. This means that the water from every faucet and showerhead in your home is filtered. Even your toilet will flush with filtered water if you have a POE system installed.
Point of use systems, on the other hand, filter less water. Under counter filters attach beneath a sink and filter all water to one or both faucets there. Faucet filters attach straight onto a faucet, and filter water as it comes out. Filter-pitchers are pitchers with in-built filters – they’re probably what you imagine when you think of an at-home filter.
Of the two filter types, POU are more popular because they tend to be considerably cheaper.
POE systems are usually based on classic filtration techniques. Within POU filter systems, several methods for filtrations are used. They are as follows:
1. Reverse Osmosis
Reverse osmosis removes almost as many contaminants as distillation. Water is pushed through an incredibly fine membrane, leaving almost all other molecules behind. RO filtered water is often remineralized once filtered, and there is also a lot of waste water created with an RO system.
2. Classic Filtration
These use a filter or series of filters made from sand, carbon, and even ceramic to capture contaminants and leave you with purified water. They can remove various impurities, ranging from simple smell and taste filters to high efficiency or heavy metals filters.
3. UV light
UV light is often used as an additional layer of filtration. UV kills bacteria and viruses without any chemical intervention.
Which of these purification techniques you use is, of course, up to you. Let both your water quality and your budget guide you, and do your research! There are a huge number of filter systems and purification methods to choose from, so it’s a big decision.
If I had the option, I would probably drink spring water straight from the source! Unfortunately, I don’t own a large plot of land dotted with springs bubbling from the mountainside, and as I don’t want to add too much to the plastic bottle problem (and I don’t want to bankrupt myself buying water) I simply use an at-home filter to purify my water instead!
This is the method I think will suit most people – you can get delicious, healthy, contaminant-free water that’s still rich in minerals straight from your tap pretty easily these days. All you need to do is choose the right filter for your needs!