What Is the Healthiest Water to Drink?

Here are some of the most common types of drinking water (1):

• Tap. This is the water you get from your taps at home. It may come from a municipal water source or a privately owned well.
• Mineral. Mineral water comes from underground sources. It naturally contains at least 250 parts per million of minerals from dissolved solids.
• Spring. Spring water is water from an underground source that rises naturally to the surface, like a spring. It must be bottled at the source.
• Distilled. Distilled water has had its minerals removed. This happens through a distillation process where the water is vaporized and then condensed back into liquid form.
• Purified water. Purified water is water that’s been treated by reverse osmosis, absolute one-micron filtration, ozonation, or distillation.

Most tap water undergoes purification processes like distillation or reverse osmosis. Meanwhile, some bottled waters may simply be unprocessed tap water. Just because water is bottled doesn’t necessarily mean it is mineral or spring water (1).

In some countries, like Australia, rural areas may depend on rainwater as a primary water source. As long as the water is tested regularly for safety, rainwater is also safe to use and drink.

Are certain types of water healthier than others?

Most drinking water in the United States is safe.

Drinking water standards are tightly regulated by the Environmental Protection Agency (EPA) and bottled water is regulated by the Food and Drug Administration (FDA) (2).

While there may be slight differences in the taste and mineral content of different types of water, for the most part, they’re equally healthy.

Downsides of certain types of water

There can be downsides to certain types of water.

All water, regardless of whether it’s bottled or from the tap, carries a risk of becoming contaminated at the source. The contaminants can be either harmless or potentially harmful pathogens like E. coli, which can cause severe gastrointestinal illness (3).

If your tap water comes from a municipal water source, it’s likely monitored and regularly tested for the presence of pathogens. However, if your tap water comes from a private well, you may need to hire an agency to regularly conduct a quality test (3).

Contaminated bottled water will be subject to recalls from the FDA.

A downside to consider relating to bottled water is the generation of large amounts of single-use plastic waste. Oftentimes, it’s unnecessary if you have access to safe tap water.

Lastly, bottled water generally also comes at a higher price point than tap water.

Thus, if you live somewhere with safe tap water, opting to drink this instead of bottled water can cut down both your expenses and how much plastic waste you generate.

Summary

There are several different types of drinking water, but all are essentially equally healthy. All drinking water carries some risk of becoming contaminated. Bottled water produces single-use plastic waste and may be more expensive.

The pH refers to the acidity or alkalinity of a liquid. A pH of 7 is considered neutral, a lower pH is more acidic, and a higher pH is more alkaline.

Most drinking water has a neutral pH of 6.5 to 7.5. Some types of water are slightly more acidic, like distilled water. Other types are more alkaline, like commercially-available alkaline waters (4).

Yet, the pH level of water doesn’t appear to make a big difference when it comes to your health.

Drinking water, regardless of its pH level, will not change your blood pH level unless you drink vast quantities that would be nearly impossible to consume (5).

Plus, in those quantities, any type of water can be dangerous because it may dilute the sodium in your blood and cause a condition called hyponatremia (5).

There’s also no recent evidence in humans to suggest that alkaline water provides any significant health benefits (5, 6).

Sometimes, an abnormally high or low pH level can indicate the contamination of a municipal water source.

If this were to affect your tap water, your water company should notify you immediately. Then, more testing would follow, and you’d be informed if their findings indicate the presence of a contaminant and how to proceed.

Summary

Most water has a pH of 6.5 to 7.5. Distilled water is more acidic, while alkaline water products are more alkaline. Drinking water cannot change your blood pH and there’s little evidence that alkaline water is better for you.

Water naturally contains minerals.

Particularly, it has calcium and magnesium, as well as negligible amounts of other minerals.

Typically, the concentration of minerals in water doesn’t affect its safety, nor is there enough of any given mineral to significantly increase your intake.

Water that’s high in minerals is referred to as hard water. It may cause deposits or stains to form in sinks or toilets and have a slightly discolored appearance.

Extra high amounts of certain minerals may cause the water to appear brown or have a distinct smell. For instance, sulfur — although safe to drink at low levels — may cause your water to smell a bit like rotten eggs (7, 8, 9).

Many water companies use softening agents to remove minerals and make the water less hard, or even “soft.” This process can instead increase the amount of phosphorus in the water, but rest assured that this is generally safe and won’t affect the water quality (8).

For clarification, water advertised as mineral water doesn’t contain added minerals. Rather, it comes from an underground source with naturally occurring minerals.

Summary

Water naturally contains some minerals, though not enough to affect your health. Hard water is higher in minerals, can cause stains, and can be discolored or smell. Mineral water contains naturally occurring but no added minerals.

Many types of water are not safe to drink.

You shouldn’t drink water from bodies of water like lakes, ponds, rivers, or the ocean.

Water from these sources can be contaminated with disease-causing pathogens or other potentially harmful contaminants. Plus, water from the ocean is too salty, so drinking it may lead to dehydration (10).

Additionally, some regions and countries may not have access to safe drinking water. Flint, Michigan is one well-known example. In 2014, the municipal drinking water in this area became contaminated with lead from corroded water pipes (11).

The nonprofit agency WaterAid also reports that less than 50% of the populations of Papua New Guinea, the Congo, Uganda, and Ethiopia have access to a basic water service (12).

If you’re unsure if the tap water is safe to drink where you are, look up local safety and quality information with the Environmental Protection Agency’s (EPA’s) Local Drinking Water Information. You may also receive an annual water quality report from your water company (13).

Drinking bottled water even if you have access to another source — like tap water — can be an unnecessary expense and generate large amounts of plastic waste. If your tap water is not safe, you should receive a notification from your water company.

Besides safety and plastic waste, another factor to keep in mind is the sugar content of some beverages.

In particular, certain types of water may contain added sugar and calories.

For example, tonic water — commonly used to make mixed drinks — is sweetened, carbonated water. Despite its characteristic bitter taste, it contains around 32 grams of sugar in a 12-ounce (366 mL) can (14).

Similarly, the brand Vitaminwater makes popular drinks that they call water beverages. These contain many ingredients in addition to just water — including added sugar (15).

While it’s alright to enjoy these beverages on occasion and in moderation, overconsumption of sugar-sweetened beverages has been linked to obesity, type 2 diabetes, and other chronic diseases (16).

The Dietary Guidelines for Americans recommend that adults limit their intake of added sugars to 200 calories or less per day. This equals 50 grams, or 12 teaspoons (17).

Summary

Avoid drinking water from ponds, lakes, rivers, and other bodies of water. Additionally, certain bottled or canned waters or water beverages may be high in added sugars.

For most people, drinking tap water is perfectly fine. It’s safe, inexpensive, and generates much less plastic waste than bottled water.

However, if your tap water is discolored, has a foul odor, or if you’ve received official communication that it’s unsafe to drink, you may need to purchase bottled water for drinking and cooking. This may be both for safety and taste preference reasons.

For example, I used to live in a small town that had brown water due to its high mineral content. We were notified it was safe to drink, but we still used bottled water for cooking, drinking, and brushing our teeth since the water had an unappetizing smell and taste.

Unfortunately, this cost can add up quickly and it does create a great deal of plastic waste. In most cases, your tap water is perfectly safe and by far the best option.

If you do need to purchase bottled water, buying refillable water cans or 5-gallon (23-liter) jugs can help cut down on plastic waste. You may be able to find these at supermarkets or home goods stores.

Summary

For most people, tap water is the best and least expensive option. However, you may need to use bottled water, at least temporarily, if your tap water is discolored, has a foul taste or smell, or is contaminated.

Tap and bottled water are subject to government oversight and regulations and are generally completely safe.

Tap water is generally a better choice because it’s less expensive and doesn’t create single-use plastic waste.

The pH level and mineral content varies between different types and sources of water, but these don’t drastically affect the overall healthfulness of the water. However, high mineral content may affect the appearance, smell, and taste of your water.

Overall, it’s best to use tap water if you’re able. However, you may need to use bottled water on occasion if you have any problems with your tap water.