Tap Water vs. Bottled Water: Which Is Better?

Summer is just around the corner, and as the temps rise you probably find yourself guzzling more and more water.

First, high five for staying hydrated! Now, here's a question: Do you quench your thirst by filling a glass from the kitchen faucet, or do you twist open bottled H2O?

Here, we investigate the pros and cons of tap versus bottled water to help you make the best decision for your health, your wallet, your taste buds and Mother Earth.

Although the Centers for Disease Control and Prevention (CDC) promises that the U.S. has some of the safest drinking water in the world, it isn't perfect. The Environmental Performance Index (EPI) Sanitation & Drinking Water report scored our agua 86 out of 100, ranking #26 in the world for quality.

A September 2020 review in the ‌Annual Review of Nutrition‌ concluded that while most tap water in the U.S. is safe, not all of it is. As the researchers noted, "drinking water can represent 20 percent or more of an individual's total lead exposure." The review calls for greater monitoring of public water systems and broader measures to protect drinking water from chemical contamination.

The purity of what comes out of your faucet also depends on where you live. Municipal water is regulated by the Environmental Protection Agency (EPA), but individual states can enforce even stricter drinking water safety standards. A February 2018 article in ‌PNAS‌ found that between 3 and 10 percent of community water systems incur drinking water quality violations each year, affecting anywhere from nine to 45 million people. Most violations happen in small, rural areas, with hotspots in the Southwest — particularly areas of Oklahoma and Texas.

What's more, the Environmental Working Group (EWG) points out that the EPA's list of chemical contaminants falls short. While the EPA sets limits on more than 90 chemical contaminants, there are more than 160 known contaminants that aren't regulated, meaning there are no rules to minimize their presence in water. These industrial or agricultural chemicals have been linked to cancer, damage to the brain and nervous system, fertility issues, abnormal fetal development and hormone disruption.

"The EPA rules are based on the information and research that was available at the time they were created," says EWG science analyst Sydney Evans. "A lot of these haven't been updated in decades and can be severely out of date."

And if you're among the 1 in 7 Americans who drink well water, know this: According to the EWG, almost one-quarter of well water contains potentially harmful levels of toxins.

"There is no federal requirement for testing private wells," Evans says. "There is this idea that it is a pristine source of water, but that is not the case." Carcinogens including radium, uranium, arsenic and nitrate are commonly found in well water. Gulp.

But here's some news to celebrate: In February 2021, the EPA committed to addressing PFAS found in drinking water. PFAS are the group of chemicals used in nonstick coating such as Teflon. They can build up in the human body and cause adverse health outcomes like elevated cholesterol. Animal studies suggest that certain PFAS can lead to reproductive and developmental issues, liver and kidney damage, cancer and more.

It's also reassuring to know that water filters can reduce the amount of many common impurities. You can opt for a Brita-style pitcher or a home tap water filter that purifies H2O straight from the faucet.

"Different types of filters can filter out different kinds of contaminants," Evans says. "So people should find out what substances they actually need to address before buying a filter."

You can see what impurities are in the water in your area by entering your zip code into the EWG's Tap Water Database. If you have a well, you should have your water tested — check out a list of laboratories by state here. To figure out what contaminants to test for, use the EWG's database to see what tends to lurk in the groundwater in your area.

At this point you might be thinking: If tap water's not necessarily clean, maybe bottled water is a safer bet. Eh, not so fast.

"There is nothing that special about bottled water — and if anything, there is a lack of transparency," Evans says.

For one thing, information about contaminants in bottled water is harder to track down. Unlike tap water, where annual testing results are disclosed to the public, the bottled water industry is not required to share their safety data. And often, it falls well below the mark.

A 2008 EWG investigation tested 10 popular water brands and found that they were all polluted with chemical contaminants, some of which exceeded legal limits. Two were indistinguishable from tap water, and four contained bacteria.

But that's not all: Substances from the bottle itself can leach into the water.

"Avoid plastics with numbers 3, 6 or 7 on the bottom, which can contain [the harmful chemicals] PVC or BPA," says registered dietician Libby Mills, RDN, LDN, national spokesperson for the Academy of Nutrition and Dietetics. "Instead, look for food-grade plastics numbered 1, 2, 4 or 5."

In addition, don't refill disposable water bottles. The packaging breaks down with use, accelerating chemical leach.

Aside from the many health benefits of hydration in general, drinking water from the faucet provides a few extra perks: "Some municipal water contains calcium and minerals, which can contribute to nutrition," Mills says.

And let's not forget about fluoride, which is in 75 percent of municipal water, according to the American Dental Association. Fluorinated water prevents more than 25 percent of tooth decay. Check here for your local water system's fluoride status.

FYI: "Filtering your water may remove fluoride," Mills says.

Sipping a bottle labeled "mineral water" might give you a slight health boost. A February 2017 study in ‌Clinical Cases in Mineral and Bone Metabolism‌ concluded that drinking it regularly can increase bone density, improve digestion and protect against metabolic syndrome.

As for fluoride, the CDC says that some bottled water might contain it, while others don't. Since manufacturers are not required to list fluoride levels on the nutrition label, the only way to find out is to contact the company directly.

Although the water itself is gratis, a filter can run you between $20 and $50 for a pitcher filter or $50 to $900 (or more) for a whole-house system, according to Food & Water Watch.

Filter cartridges need to be replaced on the reg to avoid bacteria growth. Prices range from as little as a few bucks for a carafe, faucet-mounted or under-the-sink filter to hundreds for plumbed-in systems.

According to the International Bottled Water Association, the average ‌wholesale‌ cost of a bottle of water was $1.18 per gallon in 2019. Americans guzzle 42 gallons per capita each year, making it the most popular beverage in the U.S., with sales topping $18,358 in 2018.

Engineers at Harvard University did the math and concluded that bottled H2O is about 3,000 times as expensive as good old tap.

Does your faucet spout water that's refreshing, or does it taste off?

"The flavor and smell varies from place to place depending on the different minerals and contaminants in the water," Evans says. "Still, just because your water tastes good or doesn't have an odor doesn't mean that it is necessarily clean."

If you don't love the flavor of your water, you have options. "Filtering it might improve the taste by removing some of the impurities," Mills says. Or add slices of citrus fruit, cucumber, berries, watermelon, ginger or fresh herbs like basil and mint. (Many packaged water flavorings contain chemical additives, added sugar or sweeteners, so it's best to skip those.)

Mineral water from the French or Italian Alps, the tropical islands of Fiji or a natural Maine spring sounds like it would be a flavor sensation for your mouth.

But get a taste of this: A December 2018 study in ‌Science of the Total Environment‌ found that in a blind taste test, people couldn't distinguish between tap and bottled water. Not surprising — the FDA points out that about half of bottled water is purified tap water.

Simply turn on the faucet, and you're good to go!

When you're out and about, BYO reusable bottle. What if you empty it along the way? Before purchasing a new bottle, check for a water bottle refill station. According to a September 2017 study in the ‌American Journal of Public Health‌, they're on the rise.

Or consider popping into a bar or café to request a complementary fill up. If you're concerned about drinking unfiltered water when you're out, get a reusable water bottle with a built-in filter.

Although you can pick up a bottle of water pretty much anywhere these days, it's still doesn't beat the convenience of heading over to your own sink.

According to a September 2018 report from the Massachusetts Water Resources Authority (MWRA), municipal water treatment methods use chemicals to neutralize dirt and other impurities and disinfectant like chlorine to kill bacteria, all of which take a toll on the planet. They also use energy to pump the water from the treatment plant to holding tanks and then to customer's homes.

That said, the carbon emissions, energy consumption and pollution from tap water is significantly lower than bottled water.

The MWRA reports that bottled water consumes 11 to 20 times more energy than tap, primarily due to the environmental toll of transporting the water and manufacturing the bottles.

Then there's the waste: Only 30 percent of water bottles are recycled. According to The Water Project, there are more than two million tons of plastic water bottles in U.S. landfills, and a plastic bottle takes more than 1,000 years to break down.

"Plus, as the plastic degrade, they leaches contaminants into the environment, which eventually end up in the water you are drinking," Evans says.

The winner is — wait for it — tap water, by a landslide!

"For affordability, accessibility, safety, nutrition, overall cost and sustainability, tap water is the full package," Mills says.

Just do your body a favor and filter it.