Earth is host to over 5000 varieties of minerals, so it’s no surprise that some are in your drinking water. Are they friends or foes? Spoiler alert — they’re both!
Let’s a closer look at the mineral content in your tap water and how it affects your health and home.
How Do Minerals Get into Tap Water?
Minerals are everywhere in rocks and soil. Water-soluble, they seep into surface water sources and natural underground reservoirs whenever it rains.
Not all water contains the same minerals — the types of minerals in drinking water vary based on your local geology. Most are naturally occurring, but some public water systems and bottled water manufacturers also add minerals to water for their health benefits and flavor.
What Minerals Are Found in Water?
There are trace quantities of dozens of minerals in water, but these twelve are by far the most common:
Calcium carbonate is the most abundant mineral in water. Essential for human growth and development, calcium intake is beneficial for all age groups. In children, it supports strong bones and muscles — among seniors, it prevents osteoporosis and hip fractures.
Our bodies require magnesium for more than 300 biochemical reactions at the cellular level. A must for heart function, magnesium deficiency causes weakness and fatigue. The recommended daily allowance is 310-420 mg — a target most Americans meet.
Sodium controls fluid volume and regulates the firing of nerve synapses. A double-edged sword, too little is dangerous and too much can be harmful.
We need 200 mg daily to survive, but the average American consumes more than 3000 mg per day in processed foods. High sodium levels are associated with hypertension.
Potassium regulates muscle contraction. Deficiencies are rare but can cause weakness, fatigue, muscle cramping and an irregular heartbeat.
According to the Centers for Disease Control and Prevention (CDC), Americans consume too little potassium because our intake of fresh fruits and vegetables is low. The combination of too much sodium and not enough potassium in our diets contributes to an elevated risk of high blood pressure and heart disease.
Our bodies use iron to produce red blood cells. Without it, blood carries less oxygen.
Most adults get enough iron in their diets, but teens need a boost. Iron-rich foods include red meat, shellfish and beans.
Manganese plays an important role in reproductive and bone health. Necessary for blood clotting, the recommended daily allowance averages 2 mg per day across all age groups. You’ll find it in mussels, pinto beans, hazelnuts and pecans.
Copper is among the many trace minerals we need to stay healthy. Essential for brain function, inadequate levels are associated with Alzheimer’s disease.
Top dietary sources include liver, oysters and mushrooms. But in most cases, too much copper in water is due to leaching from copper plumbing. Too much copper is risky for people with Wilson’s disease, a genetic predisposition to store too much copper in the liver and brain.
Zinc reduces oxidative stress, boosting the immune system’s ability to ward off infection. Found in red meat, poultry and fortified cereals, most people get plenty without taking supplements.
Phosphorus is essential for metabolism and pH regulation. Found in pork, turkey and seafood, it also adds structure to tooth enamel.
Like sodium, chloride is a primary electrolyte. It regulates hormone production and nerve impulses. Without it, your heart wouldn’t contract.
Most often consumed as sodium chloride — table salt — Americans get plenty in their regular diet.
Sulfur is as important for your body as calcium, supporting the regeneration of connective tissue and the production of disease-fighting antioxidants. Research suggests it cuts cancer risk. Dietary sources include broccoli, kale, legumes, garlic, onion, eggs, meat, fish and dairy products.
Sulfur in the form of hydrogen sulfide gas, however, can make your water smell like rotten eggs.
Fluoride is the world’s 13th most abundant mineral, yet it’s relatively uncommon in US groundwater. Beneficial for dental health, fluoride has been added to most public water supplies since the mid-1940s.
Current evidence, however, suggests the risks may outweigh the potential health benefits. Many people are opting to remove added fluoride with a water filter.
Are Minerals in Tap Water Regulated?
The Environmental Protection Agency (EPA) monitors mineral content in public water supplies, setting maximum contaminant levels for those with health effects, such as copper and fluoride. Most, however, are only subject to secondary drinking water standards for aesthetic effects — how they make water look, smell and taste.
The US Food and Drug Administration (FDA) regulates minerals in bottled water products labeled as:
- Bottled water
- Drinking water
- Mineral water
- Sparkling mineral water
- Spring water
- Purified water including demineralized, deionized and distilled water
Carbonated mineral water, tonic water and seltzer are regulated as soft drinks.
Does Bottled Water Contain Minerals?
The FDA defines bottled water as water for human consumption that’s sealed in bottles and contains no added ingredients. Most brands are filtered tap water, so they contain minerals and fluoride within EPA limits.
Some products, however, must meet stricter definitions. Bottled mineral waters, for example, must come from underground sources and contain at least 250 parts per million (ppm) of total dissolved solids. And all minerals must come from the source — they can’t be added later.
The most common minerals in bottled mineral water are:
- Calcium carbonate
- Magnesium sulfate
- Sodium sulfate
Manufacturers can, however, can add minerals to ordinary bottled water to balance its taste and give it a more refreshing quality, as long as they don’t label it as natural mineral water. Water with fewer than 250 ppm of total dissolved solids are called spring waters.
Does Drinking Mineral Water Have Health Benefits?
The scientific consensus is that most people get adequate mineral intake from the food they eat, but studies show that North Americans could boost their intake by over 15 percent simply by drinking tap water with high mineral content. It’s a health benefit too good to ignore.
Research shows mineral water intake may:
Improve Heart Health
Postmenopausal women who drank a liter of mineral water daily for two months lowered their bad (LDL) cholesterol (LDL) and increased their good (HDL) cholesterol. And studies of people with hypertension showed a significant decrease in blood pressure — a risk factor for cardiovascular disease — after just four weeks of daily mineral water consumption.
Low magnesium intake is associated with constipation. Magnesium draws water into the intestinal tract, aiding with regular bowel movements by relaxing intestinal muscles and improving stool consistency.
A form of magnesium is found in most over the counter (OTC) constipation remedies.
Calcium and magnesium are two popular ingredients in OTC heartburn medications. Mineral water is the treatment of choice for dyspepsia in nations across Europe.
How Can I Find Out What Minerals Are in My Drinking Water?
It’s always wise to know what’s in your tap water. If you drink from a public water source, contact your utility company for a copy of your annual consumer confidence report. Mandatory under the Safe Drinking Water Act, it tells you everything you need to know.
If you have a well, testing is up to you. The CDC recommends an annual water test for pH, nitrates, bacteria and total dissolved solids.
You can have your water tested by a local lab, but we like SimpleLab’s Tap Score test kits. They offer panels curated for both city and well water. If you drink bottled water regularly, you can even test your favorite brands. Results come with expert, unbiased advice on water treatment products.
How Do Tap Water Minerals Affect My Home?
Minerals in water may be good for your health, but too many are bad for your home.
Large quantities of calcium and magnesium in water form limescale, a chalky buildup in your plumbing system that leaves unsightly stains on your dishes, clothing and bathroom fixtures while reducing the efficiency of your water heater and appliances. Called hard water, it’s a costly issue for which you may want a water softener or water conditioner.
Iron and manganese can also cause staining, damage appliances and encourage the growth of iron and manganese bacteria, living organisms that feed on these dissolved minerals. And if you have a problem with sulfur gas, you don’t need anyone to tell you about the lingering rotten egg stench it can leave in your house.
For these problems, there are thankfully filters that offer solutions.
Minerals in water can be a blessing or a curse. As with all things in life, they’re best in moderation.