A bottle of water is just a bottle of water, right? Wrong, according to some. Celebrities and wellness TikTokkers alike can be found recommending alkaline water to tackle all manner of problems, from “detoxing” your body to slowing down aging. When there’s money to be made from promoting a bottle of the stuff, it’s worth asking the question: is there any truth to the claims?

What is alkaline water?

Alkaline water is generally considered to be water with a higher than normal pH, the scale on which we measure how acidic/basic something is. While anything above pH 7 is classed as alkaline, bottled alkaline water tends to be between pH 8 and 9, compared to the pH 6.5 to 8.5 recommended for drinking water by the US Environmental Protection Agency.

Does it have any health benefits?

“It’s more hydrating than regular water”

The claim that alkaline water is more hydrating than bog-standard water largely comes off the back of a 2017 study in which 36 male soccer players were divided into three groups: one drank highly mineralized water, the second low mineral, high alkaline water, and the third had table water. 

All had to drink around 4 liters of their assigned water type per day, for seven days, and also performed an intensive exercise routine before and after the week they had the water.

The study found that, after exercise, those who’d been consuming the low mineral alkaline water were better hydrated than the other two groups and concluded that the “results indicate that the habitual consumption of alkaline water may be a valuable nutritional vector influencing […] hydration status in active healthy adults."

In this case, however, “indicate” should be taken lightly; with 36 participants, this is a very small study. The authors even describe the data as "preliminary". Far more evidence than that, including clinical trials, would be required for doctors to start advising that we should be drinking more alkaline water if we want to up our hydration.

In the meantime, if you want to avoid getting dehydrated, a regular glass of water will do just fine.

“It can treat kidney stones”

Having kidney stones can not only be unpleasant, but cases where they’re the result of a buildup of uric acid (made when the body breaks down compounds called purines), or cystine (a derivative of the amino acid cysteine), can also require specialized therapy to bring down the acidity of your pee. The trouble is that treatment isn’t exactly cheap, and also requires patients to take tablets frequently – which means some people don’t stick to it. 

A group of researchers from the University of California, Irvine sought to find out if bottled alkaline water could make a more accessible alternative. They did so by measuring the alkaline content of five different brands of alkaline water, and compared that to the alkaline content of the tablets normally used in treatment, as well as some other beverages like orange juice, lemonade, and sports drinks, and medical supplements.

The team found that there was no added benefit to drinking alkaline water over tap water when it comes to treating the kidney stones in question. 

"While alkaline water products have a higher pH than regular water, they have a negligible alkali content, which suggests that they can't raise urine pH enough to affect the development of kidney and other urinary stones," said senior author Dr Roshan M. Patel in a statement.

“It’ll slow down aging”

Amidst some of the more… left-field approaches to anti-aging, downing some alkaline water on the reg seems quite tame – but does the science back up the claim that it’ll slow our approach to old age?

If humans were mice, then perhaps. A 2020 study found that mice supplemented with alkaline water for 10 months showed improvements in various markers of cellular aging, such as an increase in the length of telomeres – the protective structures at the end of chromosomes.

But alas, we are not rodents; while animal studies can give researchers a jumping-off point, there are a multitude of differences between mice and humans, which means that the results of this study can’t be applied to the latter. To find out if alkaline water really does affect human aging, you’d need to do plenty of long-term clinical studies in, well, humans.

Is it safe to drink?

While it might not yet have any demonstrable health benefits, if you somehow find yourself thirsty in a particularly boujie part of town with no other option besides alkaline water, you may wonder: is it safe to drink this?

For most people, a bottle now and then likely isn’t going to cause any problems – it might just taste a bit weird. However, according to Harvard Health Publishing’s Dr Howard E. LeWine, people who take medications called proton-pump inhibitors – which tackle stomach acid and bump up the pH – should be mindful.

“Adding alkaline water could raise that pH even more,” writes Dr LeWine, “and might result in an increased blood pH, which can alter the normal blood levels of chemicals like potassium, especially if they have kidney disease.”

The bottom line

While there are plenty of wild health-related claims about alkaline water, in short, there’s the opposite when it comes to evidence supporting those claims. Studies investigating its alleged benefits do exist and can even back them up – but the strength of that support isn’t enough to justify using it to manage health.

Of course, there’s nothing to stop you from picking up a bottle, but in the choice between that and regular water, you’re probably better off saving your pennies.

All “explainer” articles are confirmed by fact checkers to be correct at time of publishing. Text, images, and links may be edited, removed, or added to at a later date to keep information current.

The content of this article is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of qualified health providers with questions you may have regarding medical conditions.