For most people, no. Alkaline water is usually made by an ionizer that lifts the pH to 8, 9 or higher, but Cleveland Clinic says no empirical studies show health benefits and your body already manages its own pH. Plain water is fine, and an ionizer will not fix hard water.
What is alkaline water?
Water is measured on the pH scale, which runs from 0 to 14. USGS explains that 7 is neutral, a pH below 7 is acidic, and a pH above 7 is basic. Alkaline water sits above 7.
Cleveland Clinic says alkaline water is commonly made with an ionizer, a device that changes the chemical composition of water. The idea, it says, is to raise the pH of the water "to 8, 9 or higher." Bottled versions and countertop or under-sink ionizers are the usual ways it reaches a kitchen.
Tap water is not acidic by default. The EPA's secondary drinking water guideline range for pH is 6.5 to 8.5, so a utility's water can already sit on either side of neutral. The EPA sets those secondary standards as guidelines for taste, color and odor, says the contaminants "are not considered to present a risk to human health at the SMCL," and does not enforce them.
Does alkaline water do anything for your health?
Cleveland Clinic's dietitian addresses each common claim, and none holds up.
- Hydration. What matters is how much you drink, not which type. Cleveland Clinic says credible research is lacking for the claim that alkaline water is "more hydrating."
- Bones. The article says the FDA "has banned the use of any claims of health benefits relating to alkaline water and bone health due to insufficient evidence."
- Digestion. Once alkaline water reaches your stomach, the gastric juices will neutralize it, according to the same source.
- Illness, energy and aging. Cleveland Clinic says there have been "no empirical studies showing that alkaline water has health benefits."
On safety, the same page says your body keeps its own pH balance unless you have certain conditions such as kidney or respiratory disease, and that "Alkaline water won't do you any harm, but it also isn't a miracle in a bottle, either." If you have kidney or respiratory disease, ask your doctor before changing what you drink. That is a medical question and not a plumbing one.
Will an alkaline water system fix hard water?
No, and this is where we see people spend money in the wrong place. Hardness is dissolved calcium and magnesium. Raising the pH does not remove them. Our page on the difference between hard and soft water explains the minerals, and how hard Phoenix water is gives the local numbers.
If scale on fixtures and spots on glass are what is bothering you, the tool is a softener or a conditioner, which we compare in water softener vs. conditioner. A pH adjustment unit is a different device for a different job.
The EPA's secondary standards list also notes that high pH can bring a "slippery feel," a "soda taste" and "deposits." That is the water-quality side of the question, and it is another reason to treat pH as something to measure, not push upward for its own sake.
What should you buy instead?
Match the product to the problem you can name.
- 1Taste or chlorine smell. A certified carbon filter, covered in what kind of whole-house water filter is right for Phoenix.
- 2Specific contaminants such as lead or arsenic. A filter certified for that contaminant, as in what removes heavy metals from tap water.
- 3Scale and spotting. Treat the hardness.
- 4Not sure what is in your water. Read your city's annual report, as in how to read a water quality report.
If you already own an ionizer and like it, keep using it. Just do not expect it to do more than the sources say. If you want help sorting out what your water actually needs, we can look at your setup and give an upfront price, and the estimate is free.