What is Electrolyzed Water?
Electrolyzed water (EW) is created through a process called electrolysis, where an electric current passes through a solution, typically water with a dissolved electrolyte like sodium chloride (salt). This process creates two separate streams of water with different properties: an acidic stream at the anode and an alkaline, or reduced, stream at the cathode.
The Two Main Types: Acidic and Alkaline
- Acidic Electrolyzed Oxidizing Water (EOW): This water has a low pH (typically < 2.7), a high oxidation-reduction potential (ORP), and contains hypochlorous acid, a potent disinfectant. It is widely used in hospitals, food processing, and for sanitation due to its antimicrobial properties and is not for drinking.
- Alkaline Electrolyzed Reduced Water (ERW): Produced at the cathode, this water has a higher pH (often 8.5 to 11.5) and a negative ORP, indicating antioxidant properties from dissolved hydrogen gas (H2). This is the type that is marketed for drinking, with claims of health benefits.
The Safety of Drinking Alkaline Electrolyzed Water (ERW)
While alkaline electrolyzed water is widely promoted for consumption, its safety profile is not without important caveats.
Potential Risks of High-pH Water
According to a review published in the International Journal of Molecular Sciences, there are several safety and health concerns associated with drinking high-pH alkaline ionized water.
- Hyperkalemia: Clinical studies have linked the consumption of ERW with a pH exceeding 9.8 to dangerous hyperkalemia (high blood potassium) in some individuals, particularly those with impaired kidney function. Most manufacturers and government regulations recommend not exceeding a pH of 9.8 for drinking water.
- Electrode Degradation: Poorly made or maintained water ionizers can cause heavy metals, such as platinum nanoparticles, to leach into the drinking water. This risk increases with higher pH settings and longer electrolysis times.
- Impaired Nutrient Absorption: Consistently drinking high-pH water can neutralize stomach acid, which is crucial for absorbing minerals, vitamins, and other nutrients. This can be especially problematic for individuals already taking medications that suppress stomach acid.
- Negative Effects on Gut Microbiota: The alkalinity can potentially affect the gut microbiome, though research is ongoing.
The Truth About the "Benefits"
Many health claims associated with drinking alkaline electrolyzed water are not fully substantiated by science. The therapeutic effects, such as antioxidant properties, are now understood to be primarily from the dissolved molecular hydrogen, not the alkaline pH. This means that the high pH, and its associated risks, is not necessary to gain the potential benefits of molecular hydrogen. Newer, neutral-pH electrolytic devices aim to provide the benefits of H2 without the risks of high alkalinity.
Comparison of Electrolyzed Water Types for Consumption
| Feature | Alkaline (ERW) | Acidic (EOW) |
|---|---|---|
| Recommended for Drinking? | Yes, but with strict pH control (<9.8). | No. For sanitation only. |
| Primary Purpose | Hydration, antioxidant effects from H2. | Disinfecting and cleaning. |
| Key Active Component | Dissolved Molecular Hydrogen (H2). | Hypochlorous Acid (HOCl). |
| pH Level | Typically > 8.5. Potential for dangerous levels > 9.8. | Typically < 2.7. |
| Key Risks | High pH effects, metal leaching, nutrient malabsorption. | Not for consumption. Highly acidic and toxic. |
| Device Requirements | High-quality ionizer with proper maintenance and mineral-rich source water. | Specialized electrolysis units. |
How to Ensure Safety When Drinking Electrolyzed Water
For those considering drinking alkaline electrolyzed water produced by a home ionizer, following these best practices is crucial to mitigate risks:
- Use High-Quality Equipment: Invest in a reputable water ionizer with platinum-coated titanium electrodes to minimize the risk of heavy metal leaching. Ensure the device is regularly cleaned according to the manufacturer's instructions, often with citric acid, to prevent mineral buildup.
- Monitor pH Levels: Do not rely solely on the device's preset buttons. Test the water regularly to ensure the pH does not exceed 9.8, as recommended by regulations. Avoid drinking "strong alkaline water" with a pH over 10.
- Consult a Healthcare Professional: Individuals with kidney problems or other pre-existing health conditions should avoid consuming alkaline electrolyzed water without medical supervision, especially due to the risk of hyperkalemia.
- Prioritize Molecular Hydrogen: The claimed benefits are tied to dissolved hydrogen, not high pH. Consider alternative methods for consuming hydrogen water that do not rely on high alkalinity, such as neutral-pH electrolytic devices or hydrogen-producing tablets, to bypass the risks associated with high pH.
- Separate Cleaning and Drinking Water: Never consume the acidic water stream produced by an ionizer. Designate it strictly for cleaning and disinfecting purposes to prevent accidental ingestion.
Conclusion
While some electrolyzed water is used for sanitation and cleaning, only the alkaline variety, or electrolyzed reduced water (ERW), is promoted for drinking. Its safety depends heavily on controlling the pH to prevent high alkalinity, which has been linked to concerning health risks like hyperkalemia and impaired nutrient absorption. The primary health benefits often attributed to alkaline water, like antioxidant properties, are actually due to the dissolved molecular hydrogen, which can be obtained through safer, neutral-pH methods. Proper device maintenance and careful monitoring of pH are essential for anyone choosing to drink this water, and individuals with kidney issues should consult a doctor first.
Expert Perspective
For those seeking the potential benefits of molecular hydrogen, newer neutral-pH electrolytic devices or hydrogen-producing tablets are likely a safer, more controlled alternative to traditional alkaline water ionizers. The Food and Drug Administration (FDA) has specifically issued warnings against unregistered alkaline or oxygenated waters with unsupported health claims. The FDA approves acidic electrolyzed water for sanitizing surfaces and food contact, not for consumption. These regulations highlight the critical distinction between water used for cleaning and water safe for drinking.
