Things?
Alkaline water is a special type of water, characterized by a pH greater than 7.0.
Most bottled waters have an alkaline pH, although there may be wide differences between them in terms of fixed residue and the type of minerals they contain.
Alkaline water par excellence is ionized water , i.e. purified and processed thanks to a device called an ionizer.
Production of Ionized Water
Ionization (always preceded by filtering) is a controlled electrolysis process . It is obtained by exposing water to a low voltage current; the latter passes between two platinum-coated titanium electrodes (a positive and a negative pole), which are immersed in the liquid inside an isolated chamber.
Ionization tends to separate the cations from the anions and at the end of the process it produces two types of water.
Cations are positive ions that concentrate around the negative electrode and form cathodic or reduced (alkaline) water. Anions are negative ions that concentrate around the positive electrode and produce oxidized or anodic (acidic) water.
The two fluids come out of the machine separately and, while the ionized alkaline water is used for feeding , the acid water lends itself more to washing and cleansing (for hands , food , etc.).
What is it for?
Alkaline water is a fundamental drink (almost a progenitor) of the acid-base diet . It is a diet aimed at improving the general state of health, which should be obtained by increasing the pH of the body through the choice of “basic” foods and drinks .
Proponents of the alkaline diet claim that contemporary Western diets (for example those of North America) are highly decompensated due to an excess of ” acidic foods “.
The products responsible for lowering the physiological pH would also be guilty of the increase in the incidence of certain diseases and uncomfortable conditions such as:
- Heart problems.
- Hormonal alterations.
- Loss of muscle mass .
- Bone loss .
Water also helps determine the pH of the diet and some types show a clear tendency towards acidity; especially, tap water.
According to what the acid-base diet states, tap water is strongly acidifying and tendentially pro-oxidant, due to the polluting principles and the “wrong” minerals that characterize it.
It is no coincidence that followers of this nutritional philosophy define this type of drink as “dead water” and on the same principle they assert that alkaline water can help the body metabolise nutrients and expel toxins more effectively .
This would promote health by improving physiological performance, thanks to the buffering effect on toxic acid products accumulated in the body (which would literally be “neutralized”).
There is also a historical trace to support this hypothesis. Archaeological finds from the Rift Valley in Ethiopia indicate that hominids spent most of their evolution in this area (from Homo Ergaster to Homo Sapiens). By carrying out various samplings of the surrounding waters, it emerged that all the surrounding lakes have a strongly alkaline pH (up to 9.5-9.7), which would justify the survival and evolutionary progression of the human species.
Alkalizing Mechanism of Water
From a chemical point of view, alkaline water owes its therapeutic capacity to the oxidation-reduction potential or ORP (Oxidation Reduction Potential).
This parameter describes the ability of a molecule, ion or compound to give up electrons (by oxidizing – ORP positive) or to receive electrons (by reducing itself, becoming an antioxidant – ORP negative).
For example, the body’s natural antioxidants (for example coenzyme Q10 ) or those introduced with food (for example vitamins A , C and E) have a negative ORP.
Ultimately, thanks to its predominantly alkalizing electrolytes such as calcium , the silicate ofpotassium , magnesium and bicarbonate, alkaline water should exert a very powerful antioxidant function .
Opinion of Science
Why Foods and Drinks Can’t Change Blood pH ?
The acid-base balance of the organism is supported by a series of very effective physiological mechanisms.
Under normal conditions, the pH of the blood does not undergo significant alterations and remains in conditions of slight alkalinity, between 7.35 and 7.45.
Small but clinically significant variations in blood pH can instead be recorded in certain pathologies (usually of a renal nature or severe and decompensated diabetes ), during some pharmacological therapies or in the case of extreme dietary behaviors ( ketogenic diet and similar).
Oscillations in blood pH greater than ± 0.4 points are accompanied by severe organic damage and, in the absence of treatment, can prove lethal.
It’s different for urine
The same cannot be said about urine pH balance . These represent a very important means of excretion for the body and more precisely constitute the “blood waste”.
Acidic or basic foods and drinks are unable to alter blood pH because the regulation systems keep it in balance by neutralizing ( bicarbonate , albumin and hemoglobin ) or expelling ( pulmonary ventilation and renal filtration) the molecules potentially responsible for the alteration.
As we have seen, part of the unwanted (non-volatile) acid molecules and ions are filtered out by the kidneysand are concentrated in the urine.
Together with them, some molecules of the regulatory systems also end up in the excretory fluid; however, a selective reabsorption process also takes place, which is why urine can become significantly more acidic or basic than blood.
Other Alleged Interactions between Diet and Blood pH
Supporters of the acid-base diet and alkaline water hypothesize that the damage that can be caused by acidic foods and beverages may also be indirect.
In practice, it would not be the pH of the blood that would vary dangerously, but the concentration of some minerals normally contained in bones and muscles .
These would be used as a buffer system to counteract food acidosis, causing depletion of stocks in the long run.
Actually, blood buffer systems are mainly made up of:
- Bicarbonate-carbonic acid.
- Monobasic-dibasic phosphate.
- Albumin.
- Hemoglobin.
Followed and supported by:
- Renal control: for the excretion of fixed acidity (e.g. ketoacids).
- Pulmonary control: for the excretion of volatile acidity (e.g. carbonic acid).
The only mineral mentioned among the blood buffer systems is phosphorus which, not surprisingly, is among the salts most present in human nutrition.
It is true that renal control also involves potassium, sodium , calcium, etc.; on the other hand, based on what is mentioned in the scientific bibliography, the significant expulsion of these elements consequently increases their absorption capacity at the intestinal level (the mechanism is much more complex than it seems, given that biological systems are finely coordinated to ensure homeostasis thanks to very efficient feedback mechanisms).
Any depletion of minerals in the body can only be caused by the simultaneous presence of
- Poor intake.
- Endocrine pathologies.
- Excessive excretion (probably also of a pathological nature).
Comment
All this explains why alkaline water cannot exert any relevant effect on blood pH; at most it is able to:
- Exert a beneficial effect on the formation of certain kidney stones (but at the same time increases the risk of other types of kidney stones ).
- Contribute to electrolyte balance in the long term (it is a possible source of potassium, magnesium and calcium).
It would therefore be advisable to focus more on the quantity and type of minerals that characterize alkaline water , rather than on the final pH.
Furthermore, let’s not forget that some renal pathologies and the intake of certain drugs can easily induce the metabolic accumulation of minerals and lead to significant side effects.
Alkaline Water and Hydration
Inappropriate in case of kidney pathologies and pharmacological therapies that affect filtration or require acidic urine , alkaline water could instead be advisable for maintaining hydration.
The intake of alkaline water helps reduce urine production and blood osmolality, allowing you to maintain higher levels of hydration and ensuring blood fluidity in the cardiovascular system .
N.B. _ Recall that high plasma osmolality is associated with an increased risk of death from stroke .
These effects are not instantaneous but gradual, suggesting a hypothetical long-term benefit.
Alkaline Water and Sport
Some assume that alkaline water can help sportsmen’s performance.
During motor physical activity many hydrogen ions are produced (released from lactic acid ), which tend to lower the pH; they are normally buffered by the presence of bicarbonate-carbonic acid but are still responsible for the onset of fatigue.
Drinking alkaline water could improve buffer capacity, optimizing performance; the mechanism is the same as baking soda supplements , but does not show the same negative effects, which are:
- Gastrointestinal reactions ( diarrhea ).
- Excess sodium in the diet (predisposing hypertension in sodium-sensitive subjects and sometimes responsible for the worsening of gastritis ).
N.B. _ By reinforcing alkaline water with potassium and magnesium, greater tolerability to fatigue could be obtained , especially in long-lasting performance.
Alkaline Water and Disinfectants for Drinking
Tap water is made drinkable by a series of chemical-physical processes.
In the long term, an excess of residues left by disinfectant molecules could favor their accumulation in the body and cause negative effects on health.
With the purification and ionization process, a part of the toxins are effectively removed from the water.
However, even in alkaline water certain types of pollutants remain and in even higher concentrations.
This means that alkaline water is not necessarily a better product than plain water.
Alkaline Water and Intestinal Flora
As anticipated, the alkalization of water induces a change in the redox potential (ORP).
This appears to modify the composition of intestinal bacteria , but it is not clear whether this is limited to a selection among physiological ones or could favor the protection against pathogens.
Alkalized water and AGE
Advanced glycosylation is a non-enzymatic process that occurs in people with chronic hyperglycemia ( diabetics ).
This is a negative effect that leads to the formation of harmful products for various body tissues; these are called advanced glycation end-products (AGEs) or end products of advanced glycosylation.
A study on rats affected by high levels of AGEs has highlighted a possible protective role of alkaline water on the liver ; however it is not a real scientific evidence but rather a basis on which to deepen with further experiments.
Summary and Conclusions
| Alleged Effect of Alkaline Water | True or false? |
| Alkaline water helps treat chronic acidosis | Weak and/or speculative scientific evidence: The body regulates pH quite precisely and organs have slightly different pH requirements. There is no relevant clinical evidence that a consistently low level of acidity (compared to the physiological range) can be achieved. |
| Alkaline water improves overall health | Weak and/or speculative scientific evidence: Alkaline water is unlikely to increase overall alkalinity in the body (except in urine), and it is unclear whether this will improve health. Additionally, people with certain health conditions should avoid excessive mineral intake. |
| Alkaline water is important for athletes | Weak and/or speculative scientific evidence: Proper hydration benefits athletes, but there is no evidence that alkaline water has any additional hydration benefits. MAY have a positive effect on hydrogen ion buffering. |
| Alkaline water protects against toxins | Weak and/or equivocal scientific evidence: the alkalinization of water allows you to avoid the toxins of disinfectants in tap water, but it can accumulate others. |
| Alkaline water contains a negative redox potential, helping us protect against pathogens | Weak and/or speculative scientific evidence: ORP appears to affect bacteria in the gut . Electrochemically active (i.e. ionized) water has a negative redox potential, which means it MAY offer additional disinfectant properties , helping to select the physiological flora and protecting us from dangerous microorganisms . |
| Alkaline water reduces advanced glycosylation end products (AGEs) | Suggestive and/or speculative scientific evidence: Ionized water appears to lead to lower glycosylation levels and less liver damage only in rats with poor blood sugar control ; there is no information on humans, let alone healthy. |
Conclusion
There is little anecdotal evidence to support claims that alkaline water is beneficial to acid-base balance and bone and/or skeletal health .
The only significance of a chemical or nutritional nature concerns the relationship between mineral salts , electrolyte balance and certain forms of renal lithiasis.
It is conceivable that alkaline water can improve the overall hydration status of sportsmen in the long term, but this is only a hypothesis.
It cannot be excluded that alkaline water plays a positive role in intense physical exercise, but it is more probable that this effectiveness can be reproduced by enriching common water with sodium bicarbonate.
Thanks to the alkalinization process, the water loses a part of pollutants, but on the other hand retains others in higher concentrations.
The change in ORP affects the intestinal bacterial composition but it is not clear how and to what extent.
In some rat studies, alkalized water demonstrated a hepatoprotective effect against AGEs. There is no scientific evidence on humans and further investigations are required.
The consumption of alkaline water may be advisable for all healthy subjects who do not follow pharmacological therapies aimed at urinary regulation.
It is a valid alternative to normal water and could have some positive effects; it is said that the lack of scientific evidence corresponds to the total ineffectiveness of this product.
Among the various applications, probably the most important is in sports, although I would recommend enriching the liquid with magnesium, potassium and glucose to obtain an isotonic drink .
