Why Is Dasani Water Bad For You

Quick answer: Dasani is not spring water. It is municipal tap water that Coca-Cola runs through reverse osmosis, then re-mineralizes with magnesium sulfate, potassium chloride, and salt for taste. None of those additives is dangerous at the levels used, but independent lab testing has found an average of 325 microplastic particles per liter in major bottled water brands including Dasani, and you are paying a steep markup for reprocessed tap water in a plastic bottle. If your goal is cleaner water, filtering your own tap water gets you further for far less money.

Who makes Dasani?

Dasani is owned by The Coca-Cola Company and launched in 1999 to compete in the bottled water market. Unlike brands that bottle spring water, Dasani starts with the same municipal tap water that flows to homes and businesses, purifies it by reverse osmosis, and then adds minerals back in.

What is actually in Dasani?

The label lists four ingredients. Here is what each one is doing there.

1. Purified tap water

Dasani's source water is municipal tap water, run through a reverse osmosis (RO) filter. RO is effective purification, but it also strips out naturally occurring minerals, which is why the water needs additives to taste like anything at all. It also means you are buying back, at roughly 1,000 times the price, a version of the water already coming out of your tap.

2. Magnesium sulfate

Better known as Epsom salt, magnesium sulfate is added in trace amounts for taste. It is safe at these levels; the FDA warnings you may have read about involve high-dose medical use, not the tiny quantity in a water bottle. The fair criticism is not danger, it is that a product marketed as pure water needs mineral additives to be palatable.

3. Potassium chloride

A mineral salt used widely in the food industry, often as a sodium substitute. The amount in Dasani is far below anything clinically meaningful. Like the magnesium sulfate, its job is to make demineralized RO water taste less flat.

4. Salt

Plain sodium chloride, again for taste. The quantity per bottle is small, though it is a reasonable thing to be aware of if you drink many bottles a day or are on a sodium-restricted diet.

The bigger issue: microplastics in bottled water

A study published in Frontiers in Chemistry tested well-known bottled water brands sold in the United States, including Dasani, Aquafina, Evian, Nestle Pure Life, San Pellegrino, and Gerolsteiner. The researchers found microplastic contamination across brands, averaging 325 microplastic particles per liter. The plastic types identified, polypropylene from caps and polyethylene terephthalate from the bottles themselves, point to the packaging and bottling process as the source.

In other words, the plastic bottle is not just a waste problem. It appears to be getting into the water itself, which undercuts the main reason people buy bottled water in the first place. We cover how to reduce your exposure in our guide to microplastics from plastic water bottles.

Is Dasani bad for your kidneys, stomach, or heart?

Kidneys

There is no evidence that moderate consumption of Dasani or other RO water harms healthy kidneys. The open question researchers debate is whether relying exclusively on demineralized water over long periods shortchanges you on minerals like magnesium and calcium that hard tap water normally contributes. It is a nutrition question, not a toxicity one.

Stomach

Some people report that RO water feels harsher on an empty stomach, possibly related to its lower mineral content and slightly acidic pH. Individual sensitivity varies, and there is no evidence of harm for most people.

Heart

Minerals in drinking water play a small role in overall electrolyte intake, and some researchers argue mineral-rich water is a meaningful contributor to magnesium intake at the population level. If most of your daily water is demineralized, you are simply not getting that small benefit.

Why do people say Dasani tastes weird?

Dasani has a genuine image problem. In 2019, YouTuber Shane Dawson amplified long-running consumer complaints about the taste and the faint fizz sound some bottles make when opened, and the brand has been a running joke on TikTok and Reddit ever since. Martin Riese, the best known water sommelier in the US, has called Dasani highly processed, designed-by-focus-group factory water. The taste complaints trace back to the same root fact: it is RO water with a mineral additive package, and that engineered profile simply tastes off to a lot of people.

The bottom line

Dasani will not poison you. But you are paying a premium for reprocessed municipal tap water with additives, packaged in a bottle that sheds microplastics into the very water you are trying to keep clean, and generating single-use plastic waste with every purchase.

Filtering your own tap water solves all three problems at once. An Epic Pure XP pitcher filter is independently tested to reduce over 99.9% of microplastics along with lead, PFAS, chlorine, and other common tap water contaminants, for pennies per gallon. If you want filtered water on the go, a filtered water bottle replaces the case of Dasani entirely. You can browse all of our water filter pitchers and dispensers or grab replacement filters if you already own one.

Related reading

• Is Gatorade Zero Bad for You?
• Are Celsius Drinks Bad for You?
• Which Diet Sodas Do Not Contain Aspartame?
• Are Plastic Water Bottles Giving You Microplastics?

Sources

• Synthetic Polymer Contamination in Bottled Water — Frontiers in Chemistry
• Potential Effects of Microplastics and Additives of Concern on Human Health — NCBI
• Impacts of Plastic Pollution Across Layers of Biological Function — Frontiers in Marine Science
• FDA Drug Safety Communication on Magnesium Sulfate (high-dose medical use)
• Dietary Impact of Adding Potassium Chloride to Foods — NCBI

DASANI is a trademark of The Coca-Cola Company. This article is for educational purposes and is not medical advice.