{"id":58437,"date":"2026-10-23T15:33:44","date_gmt":"2026-10-23T15:33:44","guid":{"rendered":"https:\/\/filtrarte.com\/?p=58437"},"modified":"2026-10-23T15:50:13","modified_gmt":"2026-10-23T15:50:13","slug":"ionised-water-and-alkaline-water","status":"publish","type":"post","link":"https:\/\/filtrarte.com\/en\/ionised-water-and-alkaline-water\/","title":{"rendered":"Ionised water and alkaline water: what they are, what they are for and what science says"},"content":{"rendered":"\n

Ionised water<\/strong> and alkaline water<\/strong> are among the most searched hydration topics, and also among those surrounded by the most contradictory information. Some people present them as the answer to almost everything, while others dismiss them as a passing fad. Between these two extremes lies what the scientific evidence allows us to state today, and that is the common thread of this article.<\/p>\n\n\n\n

Understanding what they are, how they come about and what research supports helps you make informed decisions, whether out of curiosity or before considering an alkaline water appliance for your home. Throughout the text, each scientific statement names the organisation or publication it comes from.<\/p>\n\n\n\n

What alkaline water and ionised water are<\/h2>\n\n\n\n

Alkaline water<\/strong> is water with a pH above 7, the neutral point on a scale that runs from 0 (very acidic) to 14 (very alkaline).<\/p>\n\n\n\n

What pH means<\/h3>\n\n\n\n

pH measures the acidity or alkalinity of a solution. Values below 7 indicate acidity, as in lemon juice or coffee; values above 7 indicate alkalinity. Pure water sits at 7, but the water we drink is rarely pure in the chemical sense: it carries minerals and other dissolved substances that influence its pH.<\/p>\n\n\n\n

Natural alkaline water and artificial alkaline water<\/h3>\n\n\n\n

Alkaline water can have two origins. Natural alkaline water rises from aquifers rich in carbonates and silicates, where it dissolves bicarbonate and minerals from the rocks. Artificial alkaline water, on the other hand, comes from electrolysis or ion exchange, as a review published in 2026 in the scientific journal Frontiers in Medicine describes.<\/p>\n\n\n\n

Ionised water<\/strong>, also known as ionised alkaline water or electrolysed reduced water, is alkaline water that results from electrolysis in a dedicated appliance: a water ioniser, ionised water generator or alkaline water machine. All ionised water of this kind is alkaline, but not all alkaline water is ionised.<\/p>\n\n\n\n

Criterion<\/th>Natural alkaline water<\/th>Ionised alkaline water<\/th>Tap water<\/th><\/tr><\/thead>
Origin<\/strong><\/td>Springs in rocks containing carbonates and silicates<\/td>Electrolysis in a home ioniser<\/td>Public water supply systems<\/td><\/tr>
Why it has the pH it has<\/strong><\/td>Dissolved minerals, such as bicarbonate<\/td>Separation of the water into two streams by electrodes<\/td>Natural composition of the source and treatment<\/td><\/tr>
Usual pH<\/strong><\/td>Above 7, varying from spring to spring<\/td>Between 8 and 10 in the alkaline stream<\/td>Mostly between 6.5 and 8.5, according to the WHO<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

One fact that often surprises people: tap water is not always acidic. The World Health Organization (WHO) states that the pH of most drinking water lies between 6.5 and 8.5. Portuguese legislation (Decree-Law No. 69\/2023), in turn, allows values between 6.5 and 9.5 for water intended for human consumption.<\/p>\n\n\n\n

Why there is so much talk about alkaline water<\/h2>\n\n\n\n

The popularity of alkaline water rests mainly on the idea that the modern diet \u201cacidifies\u201d the body, and that what we eat and drink could correct this acidity.<\/p>\n\n\n\n

A systematic review published in BMJ Open in 2016 explains that the promotion of the so-called alkaline diet rests on this premise, known as the \u201cacid-ash\u201d hypothesis. According to this hypothesis, more fruit and vegetables and less protein would make the body more alkaline. However, the authors point out that the body tightly regulates systemic pH and that the kidneys efficiently excrete excess acid: food choices change the pH of urine, but not the acidity of the body.<\/p>\n\n\n\n

This does not take away from the value of a diet rich in fruit and vegetables, which has its own foundations. It simply means that the argument of \u201calkalising\u201d the body is not the reason why these habits make sense.<\/p>\n\n\n\n

How a water ioniser works (alkaline water appliance)<\/h2>\n\n\n\n

A water ioniser<\/strong> is an alkaline water appliance that filters the water and passes it through a chamber with electrodes, where electrolysis splits it into two streams with different pH levels.<\/p>\n\n\n\n

On the market, the same type of appliance appears under several names: alkaline water generator<\/strong>, ionised water generator<\/strong>, alkaline water machine<\/strong> or water ionisation system<\/strong>. All these names describe the same operating principle, the electrolysis of water after filtration.<\/p>\n\n\n\n

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According to the Frontiers in Medicine review, ions with an alkaline character move towards the negative electrode (cathode), where alkaline water with a pH between 8 and 10 forms. At the positive electrode (anode), by contrast, acidic water with a pH between 4 and 6 forms. The process can also generate molecular hydrogen, and the resulting water often shows a negative oxidation-reduction potential (ORP).<\/p>\n\n\n\n

In the Filtrarte range, Chanson appliances<\/a> are examples of ionisation systems for home use. The Miracle Max Plus<\/a> has a touch panel for selecting the type of water and a filter life indicator. The Miracle Max Royale<\/a> fits under the counter, leaving only the tap visible, and the tap includes a touchscreen for adjusting the pH. There is also an alternative without electrolysis: the alkalising filter<\/a> combines coconut shell carbon with a mineral formula and lets you choose between five alkalinity levels, up to a pH of 9.5.<\/p>\n<\/div>

\"Chanson<\/a><\/figure><\/div>\n\n\n\n

Alkaline water generator, alkalising filter or natural alkaline water<\/h3>\n\n\n\n

The three options reach water with a pH above 7 by different routes:<\/p>\n\n\n\n

Criterion<\/th>Ioniser or generator (electrolysis)<\/th>Alkalising filter<\/th>Natural alkaline water<\/th><\/tr><\/thead>
How it raises the pH<\/strong><\/td>Electrolysis with electrodes<\/td>Cartridge with a mineral formula<\/td>Minerals dissolved at the spring<\/td><\/tr>
pH adjustment<\/strong><\/td>Yes, through selectable levels<\/td>Yes, through alkalinity settings<\/td>No, it depends on the source<\/td><\/tr>
Power supply<\/strong><\/td>Required<\/td>Not required<\/td>Not applicable<\/td><\/tr>
Installation<\/strong><\/td>On the worktop or under the counter<\/td>Bayonet connection system<\/td>None, bought already bottled<\/td><\/tr>
Maintenance<\/strong><\/td>Periodic filter replacement<\/td>Periodic cartridge replacement<\/td>Not applicable<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

What science says about alkaline water<\/h2>\n\n\n\n

The available scientific evidence does not support most of the health claims associated with alkaline water, although some specific areas are still being studied.<\/p>\n\n\n\n

In the European Union, it is the European Food Safety Authority (EFSA) that assesses the scientific evidence behind health claims on foods. The European Commission then authorises only the claims that are based on science. For this reason, any health promise attached to a type of water deserves critical scrutiny.<\/p>\n\n\n\n

What the evidence establishes<\/h3>\n\n\n\n