For most people in the United States, filtered tap water is the best everyday drinking water. It’s regulated, affordable, environmentally lighter than bottled options, and when paired with a basic home filter, delivers clean water with a good mineral profile. But “best” depends on what you’re optimizing for: safety, taste, mineral content, or avoiding specific contaminants. Here’s what actually matters.
Tap Water: What You’re Actually Getting
Public tap water in the U.S. is regulated by the EPA under the National Primary Drinking Water Regulations, which set legal limits for over 90 contaminants. The maximum allowable level of arsenic is 0.010 mg/L. Lead triggers action at 0.015 mg/L, and if more than 10% of samples in a system exceed that level, the utility must take corrective steps. Nitrate is capped at 10 mg/L. These standards make municipal water one of the most closely monitored food products in the country.
That said, contamination can happen between the treatment plant and your faucet. Older homes with lead pipes or lead solder joints can leach the metal into water that was perfectly clean when it left the facility. Agricultural runoff can spike nitrate levels in rural systems. And while utilities are required to test and report, not every system meets every standard every year. You can check your local water quality report (called a Consumer Confidence Report) online through your utility or the EPA’s website.
Most municipal systems also add fluoride at a concentration of 0.7 mg/L, the level the U.S. Public Health Service recommends for preventing tooth decay while minimizing the risk of dental fluorosis. If you use a filter that removes fluoride, like a reverse osmosis system, keep that tradeoff in mind.
Bottled Water Types, Explained
The FDA regulates bottled water under different rules than the EPA uses for tap water, and labels like “spring,” “mineral,” and “purified” have specific legal definitions.
- Spring water comes from an underground source that flows naturally to the surface. It retains whatever minerals were present at the source.
- Mineral water also comes from an underground source but must contain at least 250 parts per million of total dissolved solids. Those minerals have to occur naturally; the manufacturer can’t add them later.
- Purified water has been treated through distillation, reverse osmosis, or a similar process to remove dissolved substances. It’s essentially a blank slate.
- Artesian water is drawn from a pressurized aquifer, where surrounding rock or clay pushes water upward when tapped. The label sounds premium, but it says nothing about mineral content or purity beyond standard FDA requirements.
None of these categories is inherently safer than well-maintained tap water. What differs is mineral content, taste, and cost.
Why Minerals in Water Matter
Water isn’t a major source of minerals for most people, but it does contribute. Assuming you drink about two liters a day, typical U.S. tap water supplies roughly 10% of your daily copper needs, 6% of calcium, 5% of magnesium, and 3% of sodium. Those numbers vary widely depending on local geology, and mineral water with higher TDS levels will contribute more.
The World Health Organization has rated water palatability by its total dissolved solids: below 300 mg/L tastes “excellent,” 300 to 600 is “good,” 600 to 900 is “fair,” and above 1,200 is generally unacceptable. But water with extremely low TDS can taste flat and unpleasant too. That sweet spot between 100 and 600 mg/L is where most people find water both refreshing and clean-tasting.
This is where purified and distilled water run into a meaningful concern. Long-term consumption of demineralized water can pull electrolytes from the body, potentially leading to low levels of sodium, potassium, magnesium, and calcium. These shifts can affect blood pressure, cell volume, and overall fluid balance. Children are especially vulnerable because they tend to drink large volumes relative to their body weight. If purified or distilled water is your primary source, adding mineral drops or getting those electrolytes through food becomes more important.
The Microplastics Problem With Bottles
One of the clearest strikes against bottled water is microplastic contamination. Research from Penn State found an average of 325 plastic particles per liter in bottled water, compared to just 5.5 particles per liter in tap water. That’s roughly 60 times more plastic in every sip from a bottle. The particles come from the packaging itself, and the gap is consistent enough across studies that it’s considered a real and measurable difference. The long-term health effects of ingesting microplastics are still being studied, but reducing exposure where you easily can is a reasonable approach.
Alkaline Water: What the Evidence Shows
Alkaline water with a pH above 7 is marketed for everything from better hydration to cancer prevention. The evidence doesn’t support those claims. Your stomach acid is so powerful that it neutralizes both regular and alkaline water to roughly the same pH within minutes. Even if alkaline water slightly shifted your blood pH, your kidneys would correct it almost immediately.
The one modest benefit: alkaline water can temporarily relieve heartburn symptoms by neutralizing some stomach acid on contact. That effect is fleeting and no different from what an antacid does. For people taking proton pump inhibitors for chronic acid reflux, drinking water with a pH above 9 could actually be dangerous, raising stomach pH too high and disrupting blood levels of potassium, particularly in anyone with kidney disease.
Home Filters: Choosing the Right Type
If tap water is the foundation, a home filter is the upgrade that makes it genuinely excellent. But different filter technologies remove different things, so the right choice depends on what’s in your water.
Granular activated carbon filters (the kind in most pitcher filters and basic faucet attachments) improve taste and remove chlorine, but they’re limited against heavy metals, pesticides, and newer contaminants like PFAS. They’re a good starting point if your water quality report looks clean and you just want better-tasting water.
Solid carbon block filters are a significant step up. They effectively reduce chlorine, volatile organic compounds, pesticides, PFAS (“forever chemicals”), microplastics, and certain heavy metals including lead. They also retain beneficial minerals, so the water doesn’t end up flat or demineralized.
Reverse osmosis systems are the most thorough option, stripping out dissolved solids, salts, fluoride, and some heavy metals. The tradeoff is that they also remove beneficial minerals and produce several gallons of wastewater for every gallon of filtered water. If you go this route, look for a system with a remineralization stage that adds calcium and magnesium back in.
The Practical Answer
For most people, the best water to drink is filtered tap water. A solid carbon block filter handles the most common concerns (lead, chlorine taste, PFAS, microplastics) while keeping minerals intact. It costs a fraction of bottled water over time and exposes you to far fewer microplastics.
If you’re on a well or in an area with known contamination, a reverse osmosis system with remineralization gives you the most control. If you prefer bottled water for convenience, mineral or spring water with a TDS between 200 and 600 mg/L will taste good and provide some mineral benefit. Avoid making distilled or purified water your sole source without supplementing minerals.
Taste, safety, mineral content, and contaminant removal all point in the same direction: start with tap, filter it well, and drink it from a glass or stainless steel bottle.