Mineral Water Guide
Mineral water and high blood pressure: what to look for on the label
Most people trying to reduce sodium look at food - but often overlook the one thing they consume every single day: water.
Mineral waters vary enormously in sodium content. Some contain less than 1 mg per liter. Others contain over 1,000 mg per liter - comparable to a portion of many processed foods.
If you drink 1.5 to 2 liters a day, the choice of water can make a meaningful contribution to your total daily sodium intake.
Sodium in water and blood pressure
The relationship between sodium intake and blood pressure is well established. Excess sodium causes the body to retain water, which increases blood volume and puts more pressure on arterial walls. Major health organizations - including the WHO and the European Society of Cardiology - recommend limiting daily sodium intake to below 2,000 mg for most adults, and lower for those with existing hypertension.
Mineral water is not the primary source of sodium in most diets - food is. But for people already making an effort to reduce sodium across all sources, water is a variable that's easy to control. Unlike food, the sodium content of mineral water is clearly printed on every label, expressed in mg per liter.
For context: drinking 1.5L per day of a water containing 500 mg/L of sodium adds 750 mg of sodium to your daily intake. Switching to a water with 5 mg/L reduces that contribution to less than 8 mg - a difference of over 740 mg per day, or roughly 37% of the WHO recommended daily limit. This is why sodium is one of the most important parameters evaluated in the h2oMatch Score when comparing mineral waters.
What 'low sodium' means on a water label
In the European Union, a mineral water can be labeled 'low sodium' if it contains less than 20 mg of sodium per liter. This is the official threshold and appears directly on the label of qualifying waters. However, not all waters below 20 mg/L are equal in practice:
| Level | Range | Note |
|---|---|---|
| Very low | < 5 mg/L | Negligible contribution even at high daily volumes |
| Low | 5-20 mg/L | Suitable for sodium-restricted diets (EU 'low sodium' threshold) |
| Moderate | 20-100 mg/L | Not labeled low sodium, but acceptable for most people |
| Moderate-high | 100-200 mg/L | Worth monitoring if managing blood pressure |
| High | > 200 mg/L | Worth avoiding if managing blood pressure |
Some sparkling and therapeutic waters - particularly those from volcanic or spa sources - can contain 500-1700 mg/L of sodium. These are sometimes marketed for digestive benefits but are not appropriate as an everyday water for people managing hypertension.
Fixed residue - the broader picture
Sodium is the most important parameter for blood pressure, but fixed residue gives you the overall mineral load. Waters with very high fixed residue (above 1500 mg/L) often contain elevated sodium and other minerals that contribute to total ionic load.
For everyday hydration under a blood pressure management regimen, fixed residue is less directly relevant than sodium, but waters with very high mineralization often also contain higher sodium levels.
The lowest-sodium mineral waters in Europe
These are the lowest-sodium natural mineral waters in the h2oMatch database, one per country:
| Water | Country | Sodium (mg/L) |
|---|---|---|
| Acqua Eva | 🇮🇹 Italy | 0.2 mg/L |
| VERI | 🇪🇸 Spain | 0.5 mg/L |
| Carpatina | 🇷🇴 Romania | 0.6 mg/L |
| Aqua Carpatica | 🇬🇧 United Kingdom | 0.6 mg/L |
| Courmayeur | 🇫🇷 France | 0.7 mg/L |
| Black Forest | 🇩🇪 Germany | 1.1 mg/L |
All waters listed contain less than 20 mg/L of sodium - qualifying as 'low sodium' under EU regulation. Source locations may differ from the country where the water is sold. All values are based on official label data.
Explore the lowest sodium waters available in your country:
What about potassium and magnesium?
Some research suggests that potassium and magnesium may support healthy blood pressure independently of sodium reduction. Potassium helps the kidneys excrete excess sodium, and magnesium plays a role in arterial relaxation.
While mineral water is not a medical treatment for hypertension, choosing a water that provides some magnesium alongside low sodium is a reasonable approach. Waters with low sodium and moderate magnesium - in the range of 10-30 mg/L - offer a balanced profile for everyday hydration. The contribution from water is relatively small compared to food, but can be a complementary factor.
Compare low-sodium waters across Europe
Use the Explore tool to find the lowest sodium mineral waters available in your country.
Explore low-sodium waters →Key Takeaway
If you are managing high blood pressure, switching to a low sodium water (below 20 mg/L, ideally below 5 mg/L) is a simple, cost-free adjustment that eliminates one variable from your daily sodium intake. It won't replace medication or dietary changes, but it removes an unnecessary source of sodium from something you consume every single day. Check the label. The sodium content is always listed. If it's above 20 mg/L, there are better options available.
FAQ
Can mineral water raise blood pressure?
On its own, low sodium water does not raise blood pressure. However, mineral waters with high sodium content - above 200 mg/L - do contribute to daily sodium intake, which can affect blood pressure in people who are sodium-sensitive or already consuming near the recommended limit. The simplest precaution is to choose a water labeled 'low sodium' (below 20 mg/L EU threshold).
Is sparkling water bad for blood pressure?
Not inherently - carbonation itself has no effect on blood pressure. The relevant factor is sodium content, not carbonation. Some sparkling waters have very low sodium levels and are perfectly suitable. Others, particularly naturally carbonated spa waters from volcanic sources, can be very high in sodium. Always check the label regardless of whether the water is still or sparkling.
How much does switching water actually matter?
It depends on the water you are currently drinking. If your current water contains 500 mg/L of sodium and you switch to one with 5 mg/L, drinking 1.5L per day eliminates roughly 740 mg of sodium from your daily intake - a meaningful amount for people on a sodium-restricted diet. If your current water is already low in sodium, the impact of switching is small.
Should I ask my doctor before changing my water?
For most healthy adults, choosing a lower-sodium water is a safe and sensible adjustment. If you are on medication for hypertension, managing kidney disease, or following a specific medical diet, it's always worth discussing dietary changes - including hydration choices - with your doctor.
This content is for informational purposes only and does not constitute medical advice.