What is the best pH water to drink?

December 15, 2025 •

4 min read

The human body maintains a tightly regulated blood pH of 7.35 to 7.45, with our kidneys and lungs constantly working to buffer against changes. This remarkable internal balance often leads to confusion about whether the pH of the water we drink truly impacts our health and whether there is an optimal level to aim for.

Quick Summary

The ideal pH for drinking water is between 6.5 and 8.5, as recommended by the EPA. While pure water is neutral at 7.0, contaminants and added minerals can alter its pH. Highly acidic or alkaline water is not recommended for consumption due to potential health and plumbing issues.

Key Points

Recommended pH Range: The Environmental Protection Agency (EPA) recommends a drinking water pH of 6.5 to 8.5 for safety and aesthetic reasons.
Alkaline Water Myths: Claims that alkaline water significantly alters body pH or cures diseases are not supported by conclusive scientific evidence, as the body has its own powerful pH regulators.
Risks of Acidic Water: Drinking water with a pH below 6.5 can be corrosive to plumbing and potentially leach harmful heavy metals like lead and copper into your water supply.
Taste and Quality: Extremely high or low pH can negatively affect water's taste, with acidic water often tasting metallic and alkaline water tasting bitter.
Focus on Purity: The most critical aspect of your drinking water is its purity and safety, not an exact pH reading. Testing for contaminants is more important than achieving a specific pH level.
Body Regulation: The human body maintains a very narrow and stable blood pH range (7.35–7.45) using the lungs and kidneys, effectively buffering any minor pH changes from food or drink.

Understanding the pH Scale

The pH scale is a logarithmic measurement that indicates how acidic or alkaline a substance is, ranging from 0 to 14. A pH of 7 is neutral, while anything below 7 is acidic and anything above 7 is alkaline, or basic. Every point on the scale represents a tenfold difference in acidity or alkalinity.

pH < 7: Acidic. Examples include lemon juice (2-3) and black coffee (5).
pH = 7: Neutral. Pure water has a neutral pH.
pH > 7: Alkaline. Examples include baking soda and milk (6.5-6.7, slightly acidic).

The Recommended Range for Drinking Water

The U.S. Environmental Protection Agency (EPA) does not regulate pH as a primary health concern, but recommends that public drinking water systems maintain a pH between 6.5 and 8.5. This range is considered safe for human consumption and ensures the water is not corrosive to plumbing or excessively bitter-tasting. The World Health Organization (WHO) also cites a similar ideal range.

The Truth About Alkaline Water

In recent years, alkaline water, often with a pH between 8 and 9.5, has gained significant popularity. Proponents claim it can neutralize body acidity, boost metabolism, and improve hydration. However, scientific evidence supporting these broad health claims is limited. Your body has robust mechanisms to maintain a stable pH regardless of the water you drink.

Potential Benefits and Risks

Acid Reflux Relief: Some studies suggest that the higher pH of alkaline water may temporarily neutralize stomach acid, providing relief for those with acid reflux.
No Significant Systemic Impact: For healthy individuals, drinking alkaline water will not change your body's overall pH balance. The kidneys and lungs are highly efficient at regulating blood pH.
Excessive Alkalinity: Chronically high intake of highly alkaline water (above 9.5 pH) could potentially interfere with stomach acid, which is vital for digestion. Individuals with kidney conditions should consult a doctor before making major changes to their water intake.

What About Acidic Water?

Water with a pH below 6.5 is considered acidic and can pose several problems.

Corrosion: Acidic water can corrode metal pipes, leaching toxic heavy metals like lead and copper into the water supply.
Aesthetic Issues: It may have a sour or metallic taste and can cause blue-green stains on plumbing fixtures.
Source: Reverse osmosis (RO) filtration, while removing contaminants, also removes minerals that act as buffers, often resulting in a slightly acidic pH of 5.5 to 7. Many modern RO systems include a remineralization stage to reintroduce minerals and balance the pH.

Comparison of Water Types and pH


Water Type	Typical pH Range	Key Characteristics
Tap Water	6.5–8.5	Varies by municipality and source. Treated with disinfectants like chlorine.
Pure Water (H₂O)	7.0	Neutral, but instantly starts reacting with atmospheric CO₂ to become slightly acidic.
Alkaline Water	8.0–9.5	Higher pH due to added minerals (calcium, magnesium) or ionization.
Spring Water	6.5–8.0	Naturally occurring pH, often with a balanced mineral content.
Distilled Water	5.5–7.0	Slightly acidic after processing, as all minerals are removed.
Sparkling Water	4.9–5.5	Acidic due to dissolved carbon dioxide.

How to Measure Your Water's pH

If you have concerns about the quality of your water, especially if it's from a private well, you can easily test its pH.

Home Test Kits: Inexpensive pH test strips or digital meters are widely available online and in hardware stores.
Professional Testing: For a more comprehensive analysis of water quality, consider professional testing services that check for heavy metals and other contaminants.

Adjusting Your Water's pH

If testing reveals a pH outside the recommended 6.5–8.5 range, particularly if it's too acidic, you can take steps to correct it.

Neutralizer Systems: For an entire home, a neutralizer tank can be installed to feed a solution like soda ash into the water, raising the pH.
Remineralization Filters: For RO or distilled water, a post-filter that adds back beneficial minerals like calcium and magnesium can effectively increase the pH.
Simple Home Methods: A small amount of baking soda can be added to water to raise its pH, but this should be done cautiously to avoid an unpleasant taste.

Conclusion: So, What is the Best pH Water to Drink?

The best water to drink for the average healthy individual is clean, pure water within the recommended EPA range of 6.5 to 8.5. This water can be from a high-quality municipal source or filtered at home. While the allure of specially marketed alkaline water is strong, the body's natural regulatory systems are far more effective at maintaining your internal pH balance. The primary goal should always be consuming safe, contamination-free water for optimal hydration, taste, and peace of mind. It is far more important to ensure your water is free from pollutants and heavy metals than to chase an unproven health fad. The scientific consensus remains that the best water is simply safe, clean, and within the broad recommended pH range.

Frequently Asked Questions

No, there is no conclusive scientific evidence to support the claim that alkaline water can cure diseases. While proponents suggest benefits, the body has efficient mechanisms to regulate its own pH, and drinking alkaline water does not alter systemic pH balance.

Highly acidic water (pH < 6.5) can be corrosive, potentially leaching toxic heavy metals like lead and copper from your home's pipes into the water. This poses a significant health risk, and the water may also taste metallic and cause plumbing stains.

No. The body has multiple, highly effective buffer systems, primarily involving the lungs and kidneys, to maintain a very stable blood pH (7.35–7.45). This process prevents minor external factors, like the pH of drinking water, from altering your internal acid-base balance.

Signs of incorrect water pH include a metallic or sour taste (low pH), a bitter or unpleasant taste (high pH), and blue-green or reddish staining on plumbing fixtures. The most accurate way to confirm is to use a home pH testing kit or professional water testing service.

RO water is often slightly acidic, with a typical pH between 5.5 and 7. This is because the filtration process removes minerals that naturally buffer the water, causing the pH to drop. Many modern RO systems include a remineralization stage to counteract this.

While distilled water is purified, it lacks minerals and can be slightly acidic, which some studies suggest may affect mineral absorption over time. For most people, it's not a concern, but regular consumption should be balanced with other mineral sources.

Yes, for minor adjustments. Adding a small amount of baking soda can increase pH, while for more persistent issues, home filtration systems with remineralization cartridges can be used. For whole-house systems, a neutralizer tank can be installed.