How Much Sodium Does a Water Softener Add to Water?
Many people know that a water softener works by replacing hard water minerals - like calcium and magnesium - with “soft” sodium ions in your water supply. However, exactly how much sodium is added to your drinking water is sometimes unclear.
For those with heart issues, high blood pressure, or just want to limit their sodium intake, it is an important question to ask - How much sodium does a water softener add to your drinking water?
The Amount of Sodium Added Depends on Water Hardness
As previously stated, a water softener will remove hard water minerals through ion exchange. Inside a water softener, there is a resin bed. Resin are little beads that filled with sodium ions. As hard water passes through the resin, the hard water minerals stick to the resin and it is replaced with sodium.
Sodium is considered a “soft” mineral because it won’t cluster or scale in your plumbing, it won’t deteriorate your water-using appliances, and it won’t leave your skin and hair dry. But, how much sodium is being added to your water as it is being softened?
The answer is - it depends.
The amount of sodium added to your drinking water depends on the initial hardness of your water. If your water is very hard - meaning it has more calcium, magnesium, and possibly other contaminants - the water softener will have to replace more hardness particles with sodium.
Conversely, if your initial water is medium or slightly hard, less sodium will be used to soften.
Below is a table that will chart how much sodium is added to a quart of water based on initial hardness. Most adults drink about a quart of water each day.
Does a Water Softener add a Dangerous Amount of Sodium to your Diet?
Even with very hard water, a water softener will not add a significant amount of sodium to your diet.
For instance, at 20 grains of hardness - some of the hardest water recorded in the US - a water softener will only add 149 mg of sodium to a quart of drinking water.
For perspective, here are the sodium contents of some common foods:
- 1 dill pickle: 930 mg
- 1 ounce of cheddar cheese: 406 mg
- 2 slices of white bread: 228 mg
- 3 ounces of sliced ham: 1,114 mg
- 1 cup of milk: 122 mg
You can see that, compared to many common food and drinks we consume every day, a water softener adds very little sodium.
Will the Added Sodium Impact my Diet?
The answer for most people is - no. The exception would be if you are on a doctor’s prescribed sodium diet for heart or blood pressure issues.
The American Heart Association recommends a diet of 2,300 mg of sodium or less per day. So, let’s do some simple math.
- >2,300 mg of sodium per day (recommended)
- 20 grains of water hardness (hardest water in the US) equals 149 mg of sodium per quart added
- Most adults drink about 1 quart of water per day
149 mg / 2,300 mg = 6% of your total daily sodium comes from a water softener
Keep in mind, this is for the hardest water in the US. For most US citizens, that number will be far less because they don’t have 20 grains of hardness initially.
For Those on a Strict Sodium Diet
We get it, not all people are OK with adding additional amounts of sodium to their diet - no matter how little.
So, they shouldn’t get a water softener, right? Wrong.
One way to provide soft water for your appliances, shower, and bath without adding sodium to your diet is to only soften your hot water line. The cold water will bypass the water softener leaving your drinking water unchanged. Meanwhile, you won’t get the scale, white spots, and dry skin when you bathe or use your washer, dishwasher, sink, and other appliances.
Also, the softener will use less energy and salt because it will be softening less water than if it were softening both hot and cold.
The Best Option
What do you do if you want soft water but don't want to drink more sodium or hard water? Install a reverse osmosis (RO) system along with a water softener.
An RO system will not only filter out the sodium added by the water softener but also a lot of other harmful contaminants like:
- Chlorine
- Flouride
- Sediment
- Herbicides
- Pesticides
- Arsenic
- Other Contaminants
An added bonus is that, by getting both a water softener and an RO system, the softener will protect the RO and extend the lifespan of the filters and membrane. The water softener will filter out hardness particles and some other contaminants before the water reaches your RO system. This means that the filters and membrane in the RO system will last longer and save you money because the water that is entering the system will be pre-treated.
So, to put this myth to bed once and for all - a water softener will not add a significant amount of sodium to your diet for most people. But, if you really want to limit your sodium intake, you can always just soften your hot water or install an RO system.