Reverse osmosis (RO) is one of the best ways to remove contaminants from drinking water. But there’s one major downside most people don’t realize until either they taste it, or they develop longer term health issues: RO removes minerals too.
And out of all the minerals stripped away during purification, one stands out as the most important — and the most commonly ignored by basic filters: magnesium.
In this guide, you’ll learn why magnesium matters in drinking water, why most remineralization filters fail to include it, and what to look for if you want clean RO water that’s not just safe, but actually healthy.
Why Magnesium Matters in Drinking Water
Magnesium is an essential mineral involved in hundreds of processes in the human body. But when it comes to drinking water, magnesium does something most people don’t expect: it dramatically improves the balance and taste, and it also improves the pH and antioxidant potential.
Water that contains magnesium typically tastes:
- cleaner and smoother
- less sharp or “empty”
- more natural, like high-quality mineral water
That’s why many premium bottled waters naturally contain magnesium — and why mineral-balanced water often feels more satisfying.
The Real Problem With RO Water: It’s Clean, But Incomplete
Reverse osmosis removes:
- chlorine
- heavy metals
- PFAS (depending on system design)
- microplastics
- dissolved solids
But it also removes:
- magnesium
- calcium
- potassium
- trace minerals
This is why RO water often tastes flat and has very low TDS. The water is clean — but it’s missing the mineral structure that makes water taste and behave like natural spring water.
Why Most Remineralization Filters Ignore Magnesium
Many remineralization filters are built around a single ingredient: calcite (calcium carbonate).
Calcite is popular because it’s inexpensive and can raise pH slightly. But calcite-only remineralization is not the same as restoring a complete mineral profile.
The biggest issue is simple: calcite adds calcium, but often adds little to no magnesium.
That means customers may still experience:
- flat taste
- mineral imbalance
- little to no antioxidant improvement
Magnesium and ORP: The Missing Link for Antioxidant Water
ORP stands for Oxidation Reduction Potential. It measures whether water behaves like an oxidant or an antioxidant.
A simple way to understand it:
- Negative ORP = a healthy antioxidant
- Positive ORP = not healthy
RO water often has a positive ORP because it is ultra-pure and stripped of minerals. This does not mean RO water is unsafe — it’s just not as healthy.
Once the water is clean, adding minerals to create higher pH and antioxidant benefits is essential. Premium remineralization blends that include magnesium can help shift RO water toward a healthier and beneficial negative ORP.
Does Magnesium Raise pH?
Magnesium-based remineralization can help increase pH naturally, but pH is not the only goal.
The real goal of remineralization is:
- restoring mineral balance
- improving taste and feel
- supporting healthier antioxidant behavior (negative ORP)
A filter that raises pH but ignores magnesium is often incomplete.
What Magnesium Does to Taste and Feel
If you’ve ever compared basic RO water to premium bottled mineral water, you’ve probably noticed something: mineral-balanced water tastes more “real.”
Magnesium is one of the key reasons why. It contributes to the smoothness and fullness of water, especially when paired with calcium.
This is why premium remineralization blends typically include both:
- magnesium (smoothness + balance)
- calcium (structure + buffering)
What to Look for in a Magnesium Remineralization Filter
If you want to add minerals back into RO water properly, avoid single-mineral solutions. Instead, look for a remineralization stage that includes:
- magnesium
- calcium
- trace minerals
The best mineral blends are designed to restore the water in a balanced way, similar to high-quality natural mineral water — but without the contaminants.
This creates a better result in:
- taste
- pH stability
- ORP behavior
- customer satisfaction
Is Magnesium Safe in Drinking Water?
Magnesium is naturally found in many spring waters. When delivered through properly designed remineralization blends, it is generally considered safe and beneficial.
The key is using a high-quality filter or mineral blend designed for drinking water. Additives like mineral drops are good for temporary or portable solutions like when traveling, but they are not cost effective to use daily or across a families water consumption.
Final Thoughts: Magnesium Is the Upgrade Most People Don’t Know They Need
Reverse osmosis is excellent at cleaning water. But healthy drinking water doesn’t stop at purification.
Once the water is clean, adding minerals to create higher pH and antioxidant benefits is essential.
And the mineral most filters ignore — but premium water solutions prioritize — is magnesium.
If your current RO system uses a basic calcite-only remineralization stage, upgrading to a magnesium-inclusive premium mineral blend is one of the biggest improvements you can make.
Clean water is step one. Mineral balance is step two.
