Can I Drink Water From A Water Softener? | Sodium & Safety

You probably know someone who refuses to drink water from the kitchen tap because of the softener. “It tastes salty,” they say, or “All that salt can’t be good for you.” That worry makes sense — water softeners work by swapping hard minerals like calcium and magnesium for sodium ions, so the idea that you’re sipping extra salt every time you fill a glass feels unsettling.

So, is that concern backed by evidence? For the majority of people, the answer is no — the amount of sodium added is typically quite small. But for anyone managing high blood pressure, kidney disease, or a doctor-prescribed low-sodium diet, the answer gets a bit more specific. This article walks through what the research says, how much sodium you’re really getting, and when you might want to bypass the softener for drinking water.

How Water Softeners Add Sodium To Your Tap Water

A standard water softener uses an ion-exchange process. Hard water flows through a resin bed coated with sodium ions. The calcium and magnesium — the minerals that cause scale buildup and soap scum — trade places with the sodium, dropping into the water instead.

The result is water with fewer hard minerals and a slightly higher sodium content. The exact amount depends on how hard your incoming water is. Very hard water requires more ion exchange, which means more sodium ends up in your glass.

How Much Sodium Are We Talking About?

Softened water usually contains about 12.5 mg of sodium per 8-ounce glass, according to some consumer health sources. For comparison, a slice of white bread has about 130 mg, and a single dill pickle can have well over 300 mg. The amount of salt added to water by a softener is trivial compared to the sodium contained in common foods eaten daily, as one industry source points out.

A study from 1997 in PubMed concluded it is unlikely that the increased sodium from softened water would pose health risks for most people, though it acknowledged that this may not be true for those on severely sodium-restricted diets. That study remains the most-cited piece of peer-reviewed evidence on the topic.

Why The Salt Scare Sticks

The concern about softened water feels intuitive — if a machine adds salt to water, and salt raises blood pressure, then drinking that water must be a problem. That logic is neat but incomplete. The real question is dose.

The American Heart Association recommends limiting total sodium to no more than 2,300 mg per day, with an ideal limit of 1,500 mg for most adults, especially those with high blood pressure. Here is how that breaks down for different drinks:

• Softened water (8 oz): Roughly 12.5 mg of sodium — less than 1% of your daily limit.
• Low-fat milk (8 oz): About 100 mg of sodium naturally.
• Vegetable juice (8 oz): Can contain 400 to 500 mg or more depending on the brand.
• Tap water before softening: Naturally contains around 9.4 mg of sodium per cup on average, per USDA data cited by some sources.

The jump from 9.4 mg to about 12.5 mg is about 3 extra milligrams of sodium per glass. For most people, that is simply not a meaningful addition to their daily intake.

Is Softened Water Safe For People With High Blood Pressure?

This is where the answer gets more personal. The sodium in softened water, while low, could still be a consideration for someone on a very strict low-sodium diet — the kind prescribed at 1,500 mg or even 1,000 mg per day for conditions like hypertension or chronic kidney disease. A Mayo Clinic discussion on sodium and kidney function notes that a high concentration of sodium in softened water forces the body to give up water to help the kidneys flush the excess, which can be a concern for those with high blood pressure.

For someone drinking eight glasses of softened water daily, the total sodium contribution would be about 100 mg. That is about 7% of a 1,500 mg daily limit — noticeable but still modest. Many doctors and dietitians suggest that if your sodium restriction is strict enough that 100 mg matters, you should consider a dedicated drinking water line that bypasses the softener.

There is also an alternative: potassium chloride softener salt. Instead of adding sodium, these systems exchange hard minerals for potassium, which can actually be beneficial for blood pressure. However, potassium-based salt is more expensive, and people with kidney disease must avoid it entirely due to the risk of hyperkalemia (excess potassium in the blood).

What Else Does A Softener Not Do?

One common misconception is that water softeners purify or filter water. They do not. Softeners address hard water minerals but do not remove contaminants like bacteria, viruses, heavy metals, or PFAS. Water treated by a softener is not unsafe to drink unless such contaminants are present in the original source water.

The Minnesota Department of Health notes that the chloride used in home water softeners can affect the water used for drinking, and that it takes only one teaspoon of sodium chloride salt to permanently contaminate 5 gallons of water. That warning refers to the brine discharge during regeneration — not the drinking water itself — but it highlights why softener maintenance matters.

So if your tap water already contains lead, nitrates, or microbial contamination, running it through a softener will not make those problems go away. A softener is a mineral-reduction device, not a water purifier. For comprehensive protection, you would need a separate filtration system — reverse osmosis being the most effective option for removing both sodium and other contaminants.

Options For Reducing Or Avoiding Sodium In Softened Water

If you want the benefits of soft water for your pipes, appliances, and skin but want to minimize sodium in your drinking water, you have several practical options.

1. Install a bypass line for drinking water. Most plumbers can run a separate tap to the kitchen sink that draws water before it reaches the softener. This gives you hard water for drinking and soft water for everything else.
2. Use a reverse osmosis system under the sink. RO systems remove 90-95% of sodium from softened water. You get the benefits of soft water for the whole house and nearly sodium-free water for drinking and cooking.
3. Switch to potassium chloride softener salt. This replaces sodium with potassium. Check with your doctor first if you have kidney concerns, but for most people it is a safe swap that adds heart-healthy potassium instead of sodium.
4. Boil your water before drinking. Boiling does not remove sodium — it actually concentrates it as water evaporates. This is not a helpful strategy for reducing sodium content.

The first two options are the most common and most effective. A bypass line is simple and low-cost, while an RO system adds a layer of contaminant removal as well.

Research Flaws And What We Still Do Not Know

The strongest evidence on softened water and health — that 1997 PubMed study — is now over 25 years old. There is limited recent peer-reviewed research looking specifically at long-term effects of drinking softened water, especially for people with mild hypertension or pre-hypertension. Most of the specific sodium-level claims come from consumer health media and brand blogs, not government agencies or large clinical trials.

Verywell Health, for instance, reports the 12.5 mg figure for an 8-ounce glass in a sodium per glass softened water guide, but that number may vary based on your home’s water hardness and softener settings. The conversation on Mayo Clinic Connect involves patient experiences rather than clinical study data, and those discussions should be taken as anecdotal perspective, not formal medical advice.

What is clear from the existing evidence is that for someone eating a standard Western diet, the sodium from softened water is a rounding error compared to processed foods, restaurant meals, and even bread. The bigger risk is not the softener — it is the rest of the diet.

The Bottom Line

Drinking water from a water softener is safe for the vast majority of people. The added sodium is minimal — roughly the same as adding a splash of low-sodium milk to your coffee. The real concern only applies if you are on a doctor-prescribed low-sodium diet for high blood pressure or chronic kidney disease, and even then, the total contribution is manageable with a bypass tap or under-sink RO filter.

A nephrologist or registered dietitian can review your daily sodium targets and help you decide whether those extra few milligrams per glass matter for your specific health situation, especially if you also have other sources of sodium in your diet that are harder to control.