When it comes to staying healthy, maintaining the proper pH keeps your body working as it should. Can drinking alkaline water help?

Most of us know that drinking water to stay hydrated is essential. Drinking water can keep your thinking sharp and mood steady, prevent your body from overheating and developing kidney stones, and keep your bowels moving. Your body needs enough of it to survive and function properly.

As you stroll through the grocery store, you may have noticed that alkaline water has taken over a large section of the beverage aisle, with various brands and flavors competing for attention. So, how is alkaline water any different from just plain water? In short, alkaline water has a higher pH level than plain water. And because of this, its proponents believe it can improve your health.

A primer on pH

Thinking back to your high school chemistry class, you might remember dipping strips of litmus paper into a solution and waiting for the color change to reveal the pH level. Put simply, pH is a measure of how acidic or basic a substance is.

To be acidic or basic means having a certain amount of hydrogen or hydroxide ions in a solution. Hydrogen ions are positively charged particles from acids, while hydroxide ions are negatively charged particles from bases. So, the more hydrogen ions a substance has, the more acidic it is. Likewise, the more hydroxide ions a substance has, the more basic it is.  

pH ranges from 0 to 14. A reading of 7 means the substance is neither acidic nor basic, or neutral. Less than 7 indicates acidic, and more than 7 indicates basic.

Let’s take some real-world examples. Pure water is neutral, which means its pH is 7. Tart liquids like lemon juice and vinegar are highly acidic, with a pH of 2. Bleach has a pH of 13, which makes it highly basic.

So, where does alkaline water fall on the spectrum?  

Alkaline water is more basic than pure water, with its pH usually around 8 or 9.

There are two types of alkaline water. Alkaline mineral water, or alkaline spring water, is naturally occurring and contains minerals such as calcium and magnesium that it gets from rocks while flowing through streams. Commercial alkaline water comes from tap water and is manufactured by a process called ionization. An electrical current changes the water’s pH by splitting up the water molecules into hydrogen and hydroxide ions and filtering out the acidic components - the finished product being less acidic water.

Alkaline diet: what are the health claims?

Advocates of alkaline water and an alkaline diet claim that the mineral components of the food we eat can elevate the acidity in the body, causing diseases like osteoporosis and cardiovascular disease. They believe lessening the acid in the bloodstream can help prevent these conditions and help manage diseases like diabetes, high blood pressure, and even cancer.

But are these health claims backed by any real science?

Here’s what the research says

Many experts agree that for most people, alkaline water is not any more beneficial than regular water and that more high-quality studies are needed to confirm the efficacy of alkaline water for human health.

For example, the theory surrounding alkaline water’s benefit for cancer stems from the idea that cancer cells and tumors flourish in a more acidic environment, so consuming a less acidic diet can prevent or even treat cancer. But does this theory hold up scientifically?

A group of scientists conducted a systematic review of available research to determine the association between the balance of a diet’s acid-inducing foods and base-inducing foods, drinking alkaline water, and cancer. The authors wanted to see how acid or base nutrient intake, including alkaline water, influences cancer incidence, recurrence, or mortality in humans. Therefore, they searched for studies published up to 2015 that analyzed this association.

Out of the 252 studies reviewed for possible matches, only one older study from 2005 met the inclusion criteria which examined the link between urine pH and bladder cancer risk among 27,096 adult Finnish male smokers. The study concluded that more acidic urine was actually associated with a lower risk of bladder cancer among this population. But as the reviewing researchers pointed out, this study had limitations. It was a prospective observational study that relied on estimated urine pH leading to potentially inaccurate results, and its finding may not necessarily apply to women and non-smokers. So, this review found that there was no solid evidence supporting the fact that reducing acid in the body by drinking alkaline water  can help with cancer prevention or treatment.

Despite the lack of research on alkaline water benefits, one area of health that alkaline water can potentially improve is hydration after exercising.

One randomized, double-blind trial evaluated the hydrating effects of alkaline water compared to regular purified water after bodily water is lost from sweating. The researchers asked 100 healthy adults to exercise using a treadmill, stationary bicycle, or elliptical trainer in an 86° room until they lost 2% of their body weight by sweating, reaching a state of dehydration. The subjects were then given either alkaline water or regular water to drink. Both groups drank water equal to 2% of their body weight within 2 hours after exercise.

The researchers then measured the subjects’ blood viscosity before and after the trial to compare how drinking each type of water impacted it. Blood viscosity, or the thickness and stickiness of blood, increases when the body is dehydrated, The results showed that the group that consumed the alkaline water saw a significant 6.30% drop in their blood viscosity compared to a 3.36% drop for those who drank regular water. So, drinking alkaline water in a dehydrated state resulted in much less sticky blood and more significant improvement in blood flow than drinking regular water. This finding led the researchers to conclude that drinking alkaline water may do a better job than regular water when rehydrating after becoming dehydrated from exercise.

The body’s natural ability to maintain pH

The evidence for alkaline water’s benefits for disease prevention is very limited, but fortunately, the body has an innate ability to maintain an acid-base balance on its own. In fact, the body aims to sustain a blood pH range of around 7.35 to 7.45, which is slightly alkaline - the optimal condition to allow for the body’s enzymes and proteins to function correctly. The body maintains its pH by using substances that bind or release hydrogen ions, changing the rate and depth of breathing which can raise pH, and excreting or reabsorbing hydrogen and bicarbonate in the urine. In other words, the body can maintain its pH without extra help. So, drinking alkaline water to lower the body’s acidity is most likely unnecessary.

The bottom line

Alkaline water has a higher pH level than regular drinking water. As a less acidic beverage, it is marketed as lowering the acid in the blood to provide various health benefits. Although some research suggests alkaline water can be more effective in rehydration after exercise-induced dehydration, there is not enough scientific evidence to support most other health claims. In addition, your body can naturally keep its pH in check all on its own. So for most people, drinking alkaline water may not be worth the extra cost and effort. Instead of buying expensive bottled alkaline water, you may be better off saving money and quenching your thirst with regular tap water.


  1. https://www.cdc.gov/healthyweight/healthy_eating/water-and-healthier-drinks.html
  2. https://www.usgs.gov/media/images/ph-scale
  3. https://www.usgs.gov/special-topics/water-science-school/science/ph-and-water
  4. https://jdh.adha.org/content/jdenthyg/89/suppl_2/6.full.pdf
  5. https://bmjopen.bmj.com/content/6/6/e010438.long
  6. https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/expert-answers/alkaline-water/faq-20058029
  7. https://pubmed.ncbi.nlm.nih.gov/16184478/
  8. https://jissn.biomedcentral.com/articles/10.1186/s12970-016-0153-8
  9. https://www.ncbi.nlm.nih.gov/books/NBK507807/