Softened water is generally safe to drink for most people, but sodium content and a few specific situations matter
Softened water has had calcium and magnesium removed through an ion exchange process, which replaces those minerals with sodium. For the average healthy adult, drinking softened water poses no health risk. However, the sodium added during softening can be a real concern for people on sodium-restricted diets, infants under six months old, and those with certain medical conditions like high blood pressure or kidney disease.
The amount of sodium in softened water depends on how hard your water was to begin with. Water that starts very hard will have more sodium added than water that is only moderately hard. A water softener that treats water with 300 parts per million (ppm) of hardness might add 100 to 150 mg of sodium per liter, while one treating 500 ppm hardness could add 200 to 300 mg per liter. For comparison, the American Heart Association recommends no more than 2,300 mg of sodium per day for adults.
Key Takeaways
- Softened water is safe for most healthy adults to drink because the sodium levels are typically low enough not to cause harm.
- People with high blood pressure, heart disease, kidney problems, or those on doctor-ordered sodium restrictions should talk to their doctor before regularly drinking softened water.
- Infants under six months should not drink softened water because their kidneys cannot handle the sodium load.
- You can reduce sodium intake from softened water by using a reverse osmosis filter on your kitchen tap or by keeping one unsoftened tap for drinking and cooking.
Who should avoid or limit softened water
Certain groups should be cautious about drinking softened water regularly. Infants under six months old have developing kidneys that cannot process sodium efficiently, so softened water should not be used to prepare their formula or drinking water. If you have an infant in your home, install a bypass on your water softener so that at least one tap delivers unsoftened water, or use bottled water for formula preparation.
Adults with diagnosed high blood pressure, congestive heart failure, cirrhosis, or kidney disease should check with their doctor before making softened water their primary drinking source. The same applies if you take medications that affect sodium balance or if your doctor has placed you on a sodium-restricted diet for any reason. Your doctor can tell you whether the sodium level in your specific softened water is a concern for your health.
People who are pregnant or breastfeeding do not need to avoid softened water based on pregnancy alone, but if you have a medical condition that requires sodium restriction, that restriction remains in place during pregnancy.
How much sodium is actually in softened water
The sodium content of softened water varies widely depending on your starting water hardness and the efficiency of your softener. You can find out exactly how much sodium your softened water contains by having it tested. Contact your local health department or a water testing laboratory—many offer affordable tests for around $25 to $75. The test will tell you the sodium concentration in milligrams per liter (mg/L) or parts per million (ppm), which are equivalent measurements.
Once you know your water's sodium level, you can calculate your daily intake. If your softened water contains 150 mg/L of sodium and you drink two liters per day, you are consuming 300 mg of sodium from water alone. For someone on a 2,300 mg daily sodium limit, that is about 13 percent of their allowance. For someone on a stricter 1,500 mg limit (sometimes recommended for people with high blood pressure), it is 20 percent—a significant portion that comes before you add any sodium from food.
Alternatives if you want to reduce sodium from softened water
If you or someone in your household needs to limit sodium but you still want the benefits of soft water for bathing and cleaning, you have several options. The simplest is to install a reverse osmosis filter on your kitchen tap. This system removes sodium along with other dissolved minerals and contaminants, producing drinking water with minimal sodium content. Reverse osmosis systems typically cost $150 to $400 for the unit plus installation, and replacement filters run $30 to $80 per year.
Another approach is to use a bypass valve on your water softener to keep one or two taps unsoftened. This is the most practical solution if you have an infant in the home. The softener treats water for your shower, washing machine, and dishwasher—where soft water saves money on soap and extends appliance life—while your kitchen sink delivers hard water for drinking and cooking. Hard water is not harmful to drink; it straightforward tastes different and may leave mineral deposits in kettles.
A third option is to use a separate salt-free water conditioner instead of a traditional softener. These systems do not remove hardness minerals but prevent them from sticking to pipes and appliances. They add no sodium and are a good choice if you want to protect your plumbing without the sodium concern. However, they do not provide the same cleaning benefits as soft water for laundry and bathing.
Minerals lost in softening and whether that matters
Water softening removes calcium and magnesium, which are minerals your body needs. However, most people get enough calcium and magnesium from food—dairy products, leafy greens, nuts, and whole grains are all good sources. Drinking hard water is not necessary to meet your mineral needs, and the amount of calcium and magnesium in drinking water is usually small compared to dietary intake.
If you are concerned about mineral intake, focus on your diet rather than your water. A glass of milk provides more calcium than a liter of hard water. A handful of almonds provides more magnesium than most people get from drinking water in a day. Softened water does not create a mineral deficiency in people who eat a reasonably balanced diet.
What the research says about softened water safety
Health organizations including the World Health Organization and the American Heart Association have found that drinking softened water is safe for the general population. The main concern they identify is sodium content for people on restricted sodium diets, which is why they recommend that people with high blood pressure or kidney disease consult their doctor.
Some older studies suggested a link between soft water and heart disease, but modern research has not supported this connection. The confusion arose because soft water is often found in areas with naturally soft water, which sometimes correlates with other environmental or dietary factors. When researchers control for those factors, no direct link between soft water and heart disease appears.
Testing your softened water and keeping records
If anyone in your household has a medical condition that requires sodium monitoring, test your water once per year. Water hardness can change seasonally, and your softener's efficiency can decline over time, so sodium levels may shift. Keep a record of test results so you can show them to your doctor and track whether your system is working as expected.
When you have your water tested, ask the lab for a full mineral analysis, not just hardness and sodium. This report will show you exactly what is in your water and help you and your doctor make informed decisions about whether softened water is right for your household. Some water testing labs offer digital reports you can email directly to your doctor's office.
Frequently Asked Questions
Can I drink softened water every day if I am healthy?
Yes. For healthy adults without sodium restrictions, drinking softened water daily is safe. The sodium levels are typically low enough not to cause concern, and softened water does not lack any nutrients your body needs from drinking water.
Does softened water taste bad?
Softened water often tastes slightly salty or flat to people used to hard water, but most people adjust within a few days. If the taste bothers you, a reverse osmosis filter or keeping one unsoftened tap can solve the problem.
Is softened water bad for plants or pets?
Softened water is safe for most pets and plants. However, some plants sensitive to sodium may show signs of stress with regular softened water watering. If you notice leaf burn or yellowing in houseplants, switch to unsoftened water or rainwater for those plants.
What if I have high blood pressure—should I stop drinking softened water?
Not necessarily. Have your water tested to find out the exact sodium level, then discuss the results with your doctor. They can tell you whether that specific amount of sodium is a concern for your situation and whether you need to switch to unsoftened water or use a reverse osmosis filter.
Can I use softened water to make baby formula?
No. Infants under six months should not consume softened water because their kidneys cannot handle the sodium. Use bottled water or unsoftened tap water for formula preparation, or install a bypass valve on your softener to keep one tap unsoftened.