Alkaline water: better than tap water?
It could be avoided: But 361.000 children under the age of five will die of diarrhea this year as well, triggered by dirty drinking water. 3 out of 10 people, or a total of 2.1 billion inhabitants of our blue planet, do not have safe drinking water in their homes. 236 million people travel at least half an hour each day to fetch water for drinking, cooking, washing, cleaning, and caring for their animals [6]
Turning drinking water into alkaline water
In Austria, no one has to live with such dangers and restrictions: In the kitchen and bathroom, clean water bubbles out of the pipes, without any need for hauling. But although the liquid necessary for survival is of excellent quality, tested and very cheap, some people do not want to consume their drinking water just like that. They prefer to make the water from the tap more basic, that is, more alkaline.
Normal drinking water, they fear, leads to unhealthy "over-acidification" of the body, as do certain foods. This supposed disturbance of the acid-base balance is said to promote diseases or even lead to cancer. There is also speculation as to whether alkaline water can support the regenerative capacity of athletes [1] [5].
Normal drinking water has a pH value of about 7 to 8. With the help of mineral additives or expensive apparatus (e.g., water purifiers), the pH value of drinking water can be lowered. B. "water ionizer") for the home, the pH value of tap water can be raised to about 9, the water becomes alkaline. Bottled ready-base water is also available for purchase. But does all this also add value to health?
Not plausible, hardly studied
The concept of such an acidification of the body is not scientifically plausible. We have already published on this in another article.
Nevertheless, we looked for studies on the question of whether alkaline water promotes health in adults without any particular pre-existing conditions, whether it prevents or cures ailments, and whether it is safe for users.
However, the results of our research were very meager. There are hardly any studies on the subject – and those that do exist are too poorly done to provide meaningful answers.
In an ideal study, the participants would be assigned to two groups by lot: one group would receive alkaline water, the other only unspectacular tap water. Appearance and taste of the two types of water should not differ, and neither participants nor study investigators should know who gets which water. The two groups of participants are likely to have differed substantially in only one characteristic: their consumption of water. For example, if the participants drinking alkaline water became ill less often afterward than those in the other group, that would be evidence of effectiveness. But we could not find such rigorously conducted studies.
So, based on the current state of studies, we cannot assess whether or what positive or negative effects regular consumption of alkaline water might have on healthy adults. However, so far it does not seem particularly plausible that significant preventive or curative effects can be achieved with it.
Safety unclear
We are also unable to make any statements about the safety of the wide range of products related to alkaline water, which is marketed mainly via the Internet. A French scientific team has criticized the fact that apparatus for quasi-unlimited alkaline water production is freely available, as opposed to medical devices with proven efficacy [3].
Very strongly alkaline water can cause toxic reactions, as shown by a 2013 incident. At that time, sodium hydroxide – an extremely basic liquid – got into the water pipes near Bonn, Germany, due to a technical defect [4].
The studies in detail
For our search, for example, double-blinded studies or cohort studies seemed ideal, in which many subjects drink alkaline water over a longer period of time in everyday life, while a comparison group only consumes unspectacular tap water.
However, the few studies we could find were anything but conclusive. Too few participants, too short durations, too little rigorous design, or sponsorship by alkaline water manufacturers (for example: [2]) make it impossible to draw reliable conclusions. For example, it is not clear whether the differently composed (and therefore not necessarily comparable) alkaline waters actually achieve the purported effect because of their high pH or because of the added minerals [1] [5].
Information on the scientific studies
[1] Fenton u.a. (2016)
Type of study: systematic review Studies analyzed: 1 cohort study Research question: Can alkaline water prevent or cure cancer?? Conflicts of interest: none according to authors
Fenton, T. R., and T. Huang. 2016. 'Systematic review of the association between dietary acid load, alkaline water and cancer', BMJ Open, 6: e010438. (Review paper in full)
[2] Weidman u.a. (2016)
Study type: randomized controlled trial Participants: 100 adults without pre-existing conditions Study duration: 1 day Research question: Does drinking alkaline water compared to ordinary water have an effect on blood viscosity?? Conflicts of interest: authors received partial funding from a company that produces alkaline water.
Weidman, J., R. E. Holsworth, Jr., B. Brossman, D. J. Cho, J. St Cyr, and G. Fridman. 2016. 'Effect of electrolyzed high-pH alkaline water on blood viscosity in healthy adults', J Int Soc Sports Nutr, 13: 45. (study in full length)
Other sources
[3] Henry u.a. (2013)
Henry, M., and J. Chambron. 2013. 'Physico-Chemical, Biological and Therapeutic Characteristics of Electrolyzed Reduced Alkaline Water (ERAW).', Water, 5: 2094-115. (Article in full length)
[4] Lendowski et al.a. (2015)
Lendowski, L., H. Farber, A. Holy, A. Darius, B. Ehrich, C. Wippermann, B. Kufner, and M.