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What Makes a Healthful Drink of Water?

Contributors: Serena Ball, MS, RDN

Reviewers: Academy Nutrition Information Services Team

Published: April 12, 2024

Reviewed: November 02, 2023

A clear glass of water on the left side of a clear bottle of water with a blue cap on a table with a blue background.
AtlasStudio/iStock/Getty Images Plus

While turning on the tap for a cool drink of water is the ultimate convenience, water also is sold in glass and plastic bottles, as well as cans and boxes.

All these options can be considered plain water, without the addition of flavors, sweeteners, caffeine or other additives (except minerals, in specific cases, which should be labeled as such).

So why are there so many types of bottled water? Which is the healthiest? And if tap water is best and least expensive, are the rest just a waste of money?

Is tap water the best and safest option?

Tap water comes from two sources: well water or a public water system.

If your water comes from a well, you are responsible for testing it yearly or more often for bacteria and other contaminants, as well as to ensure the fluoride content is sufficient for tooth decay prevention.

If you receive a water bill, your water comes from a public water system, and your municipality tests and monitors the water’s safety to ensure that standards from the United States Environmental Protection Agency are being met.

Water sources may vary in:

  • Mineral content: If mineral deposits build up on your faucets and in your dishwasher, your water is likely high in calcium and/or magnesium and is considered “hard.” Your water is “soft” if it has low levels of calcium and/or magnesium or if it has been run through an ion-exchange water softener. The mineral content also influences water’s pH, which is neutral in its purest form , but can be either acidic or alkaline (also called basic).
  • pH: The level of water acidity versus alkalinity can affect cooking and baking. For example, boiling green vegetables such as broccoli and green beans in more basic water (meaning less acidic) turns them brighter green but also can result in a mushy texture; they stay firmer in acidic water. Basic water turns vegetables that are whiter in color, such as cauliflower and white potatoes, a greyish color. Alkaline water or “hard” water with a high mineral content also can affect yeast fermentation, resulting in firmer bread; excessively acidic water can make bread dough sticky.
  • Fluoride and chlorine content: Chlorine content can be important for preventing bacterial contamination (but is not in high enough concentrations to slow yeast or sourdough activity in baking). Fluoride helps reduce the risk of developing cavities.

If you’re interested in learning more about the water in your community, ask your water utility for a water quality report.

When water leaves a municipal water supply, it’s generally very safe. However, pipes in older plumbing infrastructures can contain lead, especially in certain parts of the country. Following a federal action plan in 2021 to reduce exposure to lead in pipes and paint, the EPA issued a “Revised Lead and Copper Rule” along with guidance to aid in each state’s identification and replacement of lead service lines that are used to supply drinking water to homes and other places within communities.

If your home (and your plumbing) was constructed prior to 1986, your pipes may contain lead. Many water suppliers will test residents’ water upon request.

Exposure to lead can be especially harmful to infants, young children and individuals who are pregnant or breastfeeding. Be sure to check with your local water authority and health care provider if you or a member of your household are at increased risk and are unsure about the safety of the water in your home or community.

If replacement of lead-containing plumbing is not an option and you must rely on water from the tap, there are ways to reduce lead exposure when cooking with and drinking tap water:

  • Flush it. Let the water run the first time it’s turned on in the morning, or any time water stays in the plumbing longer than six hours. The amount of time needed to run the water can vary and will not eliminate all lead, but this step will help to reduce lead exposure. According to the EPA, water may need to run for three to five minutes for homes with a lead service line. Running water for only about 40 seconds may be needed if showering or laundry have recently been done and for homes without a lead service line.
  • Keep it cold. Don’t use hot water from the tap for cooking, drinking or for preparing infant formula, as it absorbs more lead.
  • Use a filter. While flushing is an acceptable way to reduce lead exposure, water filters that are certified for reducing lead and other minerals can help. There are different options, such as those that filter out lead but not chlorine and fluoride.

How do I know that bottled water is safe?

The U.S. Food and Drug Administration is responsible for ensuring the safety of bottled water. This can include inspecting the water source, bottling process and facility to make sure companies are following good manufacturing practices under sanitary conditions.

What are the differences between types of bottled water?

Bottled water is purified water that may be bottled at a spring, from rivers or even tap water. It may contain chlorine, fluoride or other minerals. This information isn’t usually on the bottle, so check a bottler’s website or call them.

Types of water sold in bottles include:

Distilled water: Produced by boiling tap water and collecting the condensed steam, it is free of chlorine and minerals, including fluoride.

Spring water: Collected from a source of water that bubbles up from the earth, this kind of water may or may not contain trace minerals and must be purified to remove bacteria.

Mineral water: While technically different from spring water, the two terms are often used interchangeably. According to the FDA, mineral water must contain a certain amount of dissolved minerals and other trace elements, which cannot be added later in bottling. The most common minerals in this type of water are calcium (carbonate), magnesium (sulfate), potassium and sodium (sulfate). Mineral water from an underground source naturally contains a unique composition of minerals, and it is this distinctive and variable taste that is often the reason people choose one mineral water from a certain global location over another.

The amount of minerals, such as calcium, in some waters may be as high as what is found in food and other drinks, but the serving sizes can vary. Many of these products can be a source of sodium, so be sure to review the Nutrition Facts label.

Electrolyte water: Touted as restorative after exertion in the heat, this water can vary widely in amounts of electrolytes. For a truly effective electrolyte level, look for potassium and sodium contents near that of a sports drink. Some electrolyte waters specify on the labels that electrolytes are “added for taste,” in which case they may not contain enough minerals to replace those lost in sweating.

Sparkling water: Gases (carbon dioxide or hydrogen sulfide) can be artificially added or found naturally in sparkling mineral water. Gases found naturally in mineral water are generally removed during purification and then added back to make the bottled carbonation more stable.

The FDA considers all waters with artificial carbonation (anything except naturally carbonated mineral water) to be a soft drink. This includes seltzer, soda water, club soda and “sparkling water.”

Which is the healthiest water?

Water should be consumed throughout the day, keeping in mind that different people require different amounts. The type of water you drink is mainly a personal preference. Tap water is certainly the most budget-friendly and is generally safe and a source of fluoride. There may be benefits in cooking with distilled water, and sparkling water can be an alternative to a pricier mocktail. Electrolyte or mineral waters may be a calorie-free way to replace sweat lost after a long, tough workout. While it’s unlikely that drinking one type of water over another will result in health benefits, every drop certainly counts toward meeting your fluid needs.

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