Mineral water is a genuinely healthy beverage for most people. It delivers calcium, magnesium, and bicarbonate in forms your body absorbs just as well as from food or supplements, and a growing body of clinical evidence links regular consumption to stronger bones, lower blood pressure, and better digestion. The one variable worth paying attention to is sodium: mineral waters vary enormously in their mineral profiles, and some brands contain enough sodium to matter if you’re watching your intake.
What Counts as Mineral Water
The FDA defines mineral water as underground water containing at least 250 parts per million of total dissolved solids. Those minerals and trace elements have to come naturally from the source. They can’t be added later. This distinguishes mineral water from spring water or purified water, which often contain far fewer minerals. North American spring waters average just 18 mg/L of calcium and 8 mg/L of magnesium, while North American mineral waters average around 100 mg/L of calcium and 24 mg/L of magnesium. European mineral waters sit even higher, with moderate-mineralization brands averaging 262 mg/L of calcium and 64 mg/L of magnesium.
Those differences are large enough to matter nutritionally. One liter of a moderate-mineralization European mineral water can provide 20% to 58% of your daily calcium needs and 16% to 41% of your daily magnesium needs. That’s a meaningful contribution from something you’re drinking anyway.
Your Body Absorbs These Minerals Well
A reasonable concern is whether minerals dissolved in water actually get absorbed. Clinical testing shows they do. A study comparing calcium absorption from mineral waters of different compositions against milk and a calcium supplement found no significant differences. Whether researchers measured calcium levels in the blood over 10 hours or tracked 24-hour calcium excretion through urine, the mineral water performed equally well regardless of whether it was high in sulfate or bicarbonate. This means mineral water is a practical calcium source for people who are lactose intolerant, vegan, or simply not eating enough dairy.
Effects on Bone Health
Calcium-rich mineral water does more than just supply raw calcium. It appears to actively slow bone loss. In a six-month trial, postmenopausal women with low calcium intake who drank high-calcium mineral water experienced significant decreases in parathyroid hormone (a hormone that, when elevated, signals your body to pull calcium from bones) and in biochemical markers of bone breakdown. Women drinking a low-calcium placebo water did not see those changes.
Interestingly, the type of mineral water matters. Bicarbonate-rich, alkaline mineral waters reduced bone resorption markers and parathyroid hormone levels more effectively than acidic calcium-rich waters, even when calcium intake was already sufficient. The alkalinity itself seems to play a protective role. This makes mineral waters high in both calcium and bicarbonate particularly promising for people concerned about osteoporosis.
Blood Pressure and Heart Health
Magnesium plays a central role in blood vessel relaxation, and mineral water can be a surprisingly effective way to get more of it. In a randomized, double-blind trial of 70 people with borderline hypertension, those who drank natural mineral water for four weeks saw a significant decrease in blood pressure at both the two-week and four-week marks. The effect was strongest among people who started with low magnesium or calcium levels, suggesting mineral water fills a gap that matters most when your baseline intake is low.
Sodium is the other side of this equation. Most mineral waters contain moderate sodium levels, often around 180 mg/L or less. The World Health Organization notes that taste issues start around 200 mg/L but hasn’t set a health-based limit because the contribution from drinking water is typically small. However, research published in the American Heart Association’s journal Hypertension found that each 100 mg/L increase in drinking water sodium raised systolic blood pressure by 4.5 mm Hg and diastolic by 3.3 mm Hg, and tripled the risk of developing stage 1 or 2 hypertension. If you’re salt-sensitive or managing high blood pressure, checking the label for sodium content is worth the five seconds it takes. Stick to brands under 20 mg/L of sodium if this concerns you.
Digestive Benefits
Bicarbonate-rich mineral water has a long history of use for stomach complaints, and clinical data supports it for functional dyspepsia, the kind of chronic upper-stomach discomfort that isn’t caused by an ulcer or other structural problem. In a sequential clinical trial, patients who drank 200 to 400 mL of bicarbonate-sulfate-calcium mineral water daily for 12 days experienced a significant reduction in their overall symptom score. Symptoms dropped enough to stop interfering with everyday activities. The effect held for both ulcer-like pain and the bloating and nausea typical of sluggish digestion.
The benefit appears specific to the stomach and upper digestive tract. Heartburn and lower abdominal symptoms didn’t improve significantly, suggesting the water acts directly on the stomach and duodenal lining rather than the esophagus or intestines.
Kidney Stones: Less Risk, Not More
People who’ve had calcium oxalate kidney stones sometimes worry that calcium-rich water will make things worse. The opposite appears to be true. Dietary calcium binds to oxalate in your gut before it ever reaches your kidneys, reducing the amount of oxalate that ends up in urine. A study using mineral water containing 202 mg/L of calcium and 36 mg/L of magnesium found that several key risk factors for calcium oxalate stones improved: oxalate excretion dropped, the tendency of urine to form stones decreased, and protective factors like citrate and magnesium excretion increased. Mineral water outperformed tap water on every measure tested, and the researchers concluded it deserves consideration as both a preventive and therapeutic option for stone formers.
The key distinction is between dietary calcium (from food and water, consumed with meals) and supplemental calcium taken on an empty stomach. The former reduces stone risk. The latter may increase it.
Carbonation and Your Teeth
Most mineral water is sold carbonated, which raises a fair question about tooth enamel. Carbonation lowers the pH of water, and enamel begins to soften below a pH of about 5.5. Commercial sparkling waters range from a pH of roughly 4.2 to 5.9, meaning some sit below that threshold.
Lab studies show that highly carbonated water does reduce enamel hardness more than still water. But the picture is more nuanced than “bubbles are bad.” Lightly carbonated water caused significantly less enamel change than heavily carbonated water. And when calcium was present in the carbonated water (as it naturally is in mineral water), enamel softening dropped further. Lightly carbonated water with calcium ions produced enamel changes that were not significantly different from plain water. So naturally carbonated mineral water, which tends to be lightly fizzy and calcium-rich, poses far less concern than a heavily carbonated soda water with no mineral content.
Choosing a Mineral Water
Not all mineral waters are created equal. North American brands tend to be lower in minerals overall, sometimes not much different from tap water. European brands like those from France, Italy, and Germany typically contain substantially more calcium, magnesium, and bicarbonate. If you’re drinking mineral water partly for its mineral content, the label is your guide.
- For bone support: look for calcium above 200 mg/L and high bicarbonate content.
- For blood pressure: choose brands high in magnesium and low in sodium (under 20 mg/L).
- For digestion: bicarbonate-rich varieties (look for HCO3 on the label) are the most studied.
- For kidney stone prevention: calcium and magnesium together are ideal. Drink it with meals.
Tap water isn’t nutritionally empty, especially from groundwater sources, which average around 52 mg/L of calcium and 20 mg/L of magnesium in North America. But mineral water can deliver three to five times those amounts per liter, making it a practical way to close gaps in your mineral intake without changing your diet or adding supplements.