Alkaline Water: Miracle or Marketing?

High-pH water is touted for many health benefits. Learn what it’s mostly likely good for.  

Updated by Linda Rath | April 25, 2023

Post-pandemic sales of alkaline water are booming, with revenues expected to top $1.3 billion in 2023. Even big-box retailers like Costco are getting in on the action, putting out their own alkaline water brands. Is this just great marketing or is alkaline water actually healthier?

Alkaline water is water that has been treated to have a higher-than-normal pH — a measure of acidity and alkalinity. The pH (potential hydrogen) scale ranges from 0 (extremely acid) to 14 (extremely alkaline). Seven is considered the neutral sweet spot, and it’s what the Environmental Protection Agency recommends for municipal tap water. Alkaline water usually has a pH of 8 or 9. 

To qualify as alkaline, bottled water must contain alkalinizing minerals like calcium and magnesium carbonate and have negative oxidant reduction potential, meaning it should act as an antioxidant, something like blueberries or fish oil.  

But Is It Healthy?

Like many things in gray nutritional areas, there is lots of hype around alkaline water, but not much science. There is no evidence, for example, that it prevents or cures cancer — an idea that may have originated in studies showing that cancer cells thrive in an acidic environment. There is also no evidence that it postpones aging, increases collagen production (although collagen supplements may) or cleans out pores. Healthy skin is naturally acidic, so it’s not clear why drinking alkaline water would improve it.

There are, however, a handful of studies that suggest higher-pH water might help with digestion, bone health and hydration, although experts say there isn’t enough evidence to draw firm conclusions.

Acid reflux. A 20-year-old test tube study found that alkaline water with an 8.8 pH — common in most commercial alkaline water — permanently neutralized stomach acid (pepsin), thereby relieving acid reflux symptoms. Based on those findings, a 2017 trial involving 184 patients pitted alkaline water plus a Mediterranean diet against proton pump inhibitors (PPIs), the most common medication for acid reflux. Results showed that PPIs were no better at controlling acid reflux than diet and alkaline water, although the diet seemed to do the most good. This is an important finding because PPIs were once routinely prescribed to arthritis patients to help prevent bleeding ulcers from nonsteroidal anti-inflammatory drugs (NSAIDs). It’s now known that PPIs can also have serious side effects, including a serious, potentially fatal intestinal infection, dementia and a significantly heightened risk of autoimmune disease. The study authors suggest that alkaline water and a plant-based diet may be a better treatment for acid reflux disease than medication.

Bone health. Bones are exquisitely sensitive to changes in pH. In an acid environment, new bone doesn’t form while existing bone breaks down. Bones even have alkaline reserves to offset excess acidity. Some researchers have speculated that alkaline water might protect bones, especially in postmenopausal people. In a 2021 study, researchers compared bone strength and density in two groups of postmenopausal people with osteoporosis. One group received a daily supplement of calcium and vitamin D plus a little over six cups of alkaline water along with 70 mg a week of alendronate (Fosamax), a drug intended to increase bone density. The control group took only the vitamin supplement and alendronate. After three months, both groups had improvements in bone density, but bone density in the spine improved significantly more in the alkaline water group. Interestingly, these findings were replicated a year later in an animal study, which would likely have gone unnoticed had it not been preceded by a human one.

Hydration. A big selling point of alkaline water is that it’s extra hydrating. One study of 100 healthy adults did find that alkaline water was twice as hydrating as regular water after exercise.

Alkaline water, while not a miracle cure, isn’t harmful. It can be expensive, but may be worth a try, especially as a replacement for PPIs along with an anti-reflux diet.

Stay in the Know. Live in the Yes.

Get involved with the arthritis community. Tell us a little about yourself and, based on your interests, you’ll receive emails packed with the latest information and resources to live your best life and connect with others.