Is Alkaline Water Good for You? What the Science Says - GoodRx (2024)

Alkaline water is a popular type of bottled water that you can find in convenience stores and grocery stores. Like other water, it’s calorie-free and hydrating. It may have some health benefits too. But buyer beware: Some health claims that companies make about alkaline water are unproven.

Read on to learn more about alkaline water — and which health benefits are true and which are hype.

What’s alkaline water?

Alkaline water has a higher pH than tap water. This means it’s less acidic. It’s marketed as being healthier than regular water because of its higher pH.

The pH scale measures the acid or base (alkaline) level of substances of all kinds, from chemicals to beer. The term pH stands for “potential of hydrogen.” It measures the amount of hydrogen ions in a substance. More hydrogen ions make a substance more acidic.

The pH scale ranges from 0 (very acidic) to 14 for (least acidic). For reference, here are some common drinks and items and their pH:

• Orange juice and soda: 3

• Pure water: 7 (neutral)

• Baking soda: 9

Alkaline water has a pH of about 8 to 10.

Alkaline water can be naturally occurring or machine-made. Natural alkaline water is created when spring water flows over rocks and picks up trace amounts of minerals. Machine-made alkaline water is made through a process called water electrolysis.

In water electrolysis, regular water is treated in an ionizer. This is a machine that separates water molecules into acidic and basic parts, then removes some of the acid. This treatment increases the pH of the water from neutral (7) to about 8 to 10 (alkaline).

Some people buy ionizers for home use to turn their tap water alkaline. But these machines can be expensive, ranging from a few hundred to several thousand dollars.

How is alkaline water different from regular tap water?

As mentioned above, with its higher pH range, alkaline water is less acidic than tap water. Studies show that any potential beneficial effects of alkaline water are due to the higher pH.

Some alkaline water may contain trace minerals, such as calcium and iron. But “trace” is the key word here. These minerals are found in such small amounts that they don’t contribute to your nutrient needs in any meaningful way.

The nutrition label for most brands of alkaline water lists 0 mg for potassium, calcium, and iron. The label usually says in fine print: “Not a significant source of nutrients.” In the end, alkaline water’s nutrition content is the same as tap water.

What are the potential health benefits of alkaline water?

Here’s what the science says about some of the potential benefits of alkaline water.

Heartburn and acid reflux

One study found that drinking alkaline water along with eating a plant-based Mediterranean diet may help reduce acid reflux. However, it’s difficult to tell whether the relief from acid reflux was due to the plant-based diet more than the alkaline water. More studies are needed to determine whether alkaline water really makes a difference, or if the plant-based diet is the real hero.

Another study found that alkaline water helped treat heartburn. However, this study was funded by an alkaline water manufacturer, so it may be biased. So, until experts know more, it’s probably better to try heartburn treatments with proven benefits.

Hydration

All water is hydrating. But some brands of alkaline water claim their water provides better hydration than tap water.

One study tested the hydration effect of alkaline water on healthy adults after they exercised. The researchers found that alkaline water seemed to provide better rehydration than tap water — as measured by how concentrated their blood was. But it’s unclear if more diluted blood has any meaningful impact on total body hydration status. So, more studies are needed.

Bone health

There may be some links between drinking alkaline water and bone health. In one study, women with osteoporosis drank alkaline water over a 3 month span. They also used traditional treatments for osteoporosis. The women had better spinal bone density compared to those who took medications alone.

So, if you have osteoporosis, it may help to drink alkaline water. But make sure you’re still taking any medications or supplements recommended by your healthcare professional.

What health claims about alkaline water have no proof?

Many companies sell alkaline water or expensive ionizer machines, so people can make alkaline water at home. Some claim that alkaline water can prevent diseases or slow aging. But there’s no science to support these more exaggerated claims. As always, if it sounds too good to be true, it usually is.

Here are some of the common health claims about alkaline water that aren’t backed by science.

Cancer

Alkaline water can’t prevent or treat cancer. This is a dangerous claim, especially if it draws attention away from prevention and treatment strategies that do work.

You can make lifestyle changes to minimize your risk of cancer or cancer returning, such as:

• Following a plant-based or Mediterranean diet

• Finding and maintaining a comfortable weight for you

• Exercising regularly

• Avoiding tobacco products

• Reducing alcohol

Aging

Aging is a natural part of living. No food, drink, or supplement can halt the aging process. Some companies claim their alkaline water slows down aging by reducing oxidative stress. This is a clever marketing strategy, since it’s hard to prove the claim isn’t true. But you should be wary of any product that claims to slow down aging.

Detoxification

Some companies claim that alkaline water can detoxify the body. They don’t say which toxins are targeted or how this works. Similar to the anti-aging claim, this is a marketing ploy that can’t be verified.

Kidney stones

One treatment that helps prevent certain kinds of kidney stones is a medication called potassium citrate. It works by increasing the pH of urine. So, scientists tested whether alkaline water could be an easier way to raise urinary pH. They found that the alkali content of water was too low to raise urine pH enough to combat kidney stones. So, alkaline water isn’t helpful for preventing kidney stones.

Acidic body pH

Some diseases, such as cancer and diabetes, can cause the body to be more acidic. So, some people have wondered if alkaline water may help lower the body’s acid level — and in turn help combat those diseases. Unfortunately, it’s not that simple.

Despite the claims, alkaline water doesn’t alter the pH of the body, either in the blood or urine. And the truth is, you wouldn’t want alkaline water to have the ability to change your body’s pH. Your kidneys, lungs, and liver are a built-in filtration system to keep your body at the right pH of about 7.4. And all your organs and cells depend on that pH to function. In fact, a blood pH level below 6.8 or above 7.8 can be fatal.

Gut health issues

One systematic review of 10 articles compared alkaline water to regular mineral water. The researchers found that alkaline water didn’t make any difference in gut bacteria or the microbiome. That means it didn’t help produce beneficial gut bacteria. But it didn’t destroy bacteria either.

So, there’s currently no evidence to suggest that alkaline water has any noticeable effect on your gut microbiome.

Are there downsides to drinking too much alkaline water?

Alkaline water is safe. And just like water, it helps hydrate you. The higher pH isn’t a problem for most people. The human body makes changes to regulate its pH level as needed.

In very large quantities, alkaline water may cause overhydration. But this can happen with too much of any fluid. So it’s important to drink alkaline water as you would normal water.