Yes, spring water contains magnesium, but typically in small amounts. North American spring waters average around 8 mg/L of magnesium, which is far less than what you’d get from foods like nuts, leafy greens, or beans. The exact amount varies dramatically depending on the geology where the spring originates, ranging from nearly zero to about 50 mg/L.
How Much Magnesium Is in Spring Water
A study in the Journal of General Internal Medicine analyzed 28 North American spring water brands and found an average magnesium concentration of just 8 mg/L. That’s a small number compared to the daily recommended intake of roughly 400 mg for adults. Even drinking two liters of average spring water per day would give you about 16 mg, or around 4% of what your body needs.
The range, however, is wide. Some spring waters contain less than 1 mg/L while others reach nearly 50 mg/L, depending on where the water comes from. A study of Turkish bottled spring waters found magnesium concentrations ranging from 0.4 to 49.7 mg/L, with an average of 24.1 mg/L. Geography matters enormously here. The EPA estimates that typical drinking water in the United States provides less than 10% of the recommended daily magnesium intake.
Why the Amount Varies So Much
The magnesium in spring water comes from the rocks the water flows through underground. When rainwater seeps into the earth, it slowly dissolves minerals from the surrounding rock through a process called weathering. Rocks rich in magnesium, like serpentinized peridotite and other ultramafic formations, release significantly more magnesium into groundwater. Springs near these geological formations produce water with higher magnesium concentrations.
This is also why mineral water tends to contain more magnesium than spring water. Mineral waters often come from areas near geothermal regions with deep groundwater circulation and volcanic or tectonic activity, where water spends more time in contact with mineral-rich rock at higher temperatures. On average, bottled mineral waters contain about twice the magnesium of spring waters. In the Turkish comparison study, mineral waters averaged 44.3 mg/L versus 24.1 mg/L for spring waters, and major mineral concentrations were 2 to 14 times higher overall.
Spring Water vs. Mineral Water vs. Filtered Water
If magnesium content matters to you, the type of water you choose makes a real difference. In the U.S., the FDA requires “mineral water” to contain between 500 and 1,500 mg/L of total dissolved solids, which includes a mix of minerals like calcium, sodium, and magnesium. Spring water has no such minimum. That’s why spring water brands vary so widely, and many contain barely measurable amounts of magnesium.
Filtered water sits at the opposite end of the spectrum. Reverse osmosis systems, which are popular in homes and used in many purified bottled waters, remove about 96% of magnesium from water. A spring water that starts with 25 mg/L of magnesium would end up with roughly 1 mg/L after reverse osmosis. Distillation strips minerals even more thoroughly. If your home uses one of these systems, your drinking water contributes almost nothing in terms of magnesium.
One thing worth noting about labeling: the FDA does not require bottled water brands to list magnesium on their nutrition labels unless they make a specific claim about it. So the absence of magnesium on a label doesn’t mean the water contains none. Some brands voluntarily list mineral content, while others don’t. If you want to compare, check the brand’s website or look for a water quality report.
Your Body Absorbs Magnesium From Water Efficiently
The upside of water-based magnesium is that your body absorbs it well. A study in healthy young women found that roughly 46% of the magnesium from mineral water was absorbed when consumed on its own, and about 52% when consumed with a meal. That’s comparable to or better than absorption rates from many food sources, where magnesium is often bound to fiber or other compounds that slow uptake.
So while the total amount of magnesium in spring water is modest, what’s there gets used efficiently. Drinking magnesium-rich water with meals boosts absorption by about 14%, making it a reasonable supplemental source even if it can’t replace dietary intake.
Does the Magnesium in Water Affect Health
A large population-based cohort study published in The American Journal of Clinical Nutrition found that drinking water with higher magnesium concentrations was associated with a 31% lower risk of ischemic stroke in postmenopausal women when comparing the highest intake group to the lowest. Calcium in the water was also studied, but when the researchers separated the two minerals, only magnesium remained significantly linked to reduced stroke risk. The connection to heart attacks was less clear and not statistically significant.
The biological explanation lines up with what’s known about magnesium more broadly. The mineral helps relax blood vessels, has anti-inflammatory properties, and contributes to healthy blood pressure regulation. High blood pressure is one of the strongest risk factors for stroke, so even modest additional magnesium intake from water could contribute to a meaningful reduction in risk over time.
That said, spring water alone won’t fix a magnesium shortfall. Most of your daily magnesium should come from food: a single ounce of almonds provides about 80 mg, a cup of cooked spinach delivers around 157 mg, and half a cup of black beans offers roughly 60 mg. Spring water is best thought of as a small, steady contributor rather than a primary source.
How to Find Higher-Magnesium Spring Water
If you want spring water with meaningful magnesium content, look for brands that list mineral composition on the label or on their website. European spring and mineral waters tend to have higher mineral content than North American brands, partly due to different geological formations and partly because of stricter labeling requirements in the EU that make mineral content easier to compare. Some European brands contain over 100 mg/L of magnesium.
Among U.S. brands, look specifically for “mineral water” rather than “spring water” if magnesium is your priority. The mandatory minimum of 500 mg/L total dissolved solids doesn’t guarantee high magnesium specifically, but it does increase the odds. And avoid purified or reverse-osmosis-treated waters if mineral content is important to you, since the filtration process strips out almost everything.