Is Still Water Mineral Water? Understanding the Difference

December 17, 2025 •

3 min read

According to the FDA, natural mineral water must contain a minimum of 250 parts per million of total dissolved solids from its source. A common point of confusion for many consumers is whether still water is mineral water, or if they are two distinct types of drinking water. The answer is nuanced, as some mineral waters are still, but not all still water is mineral water. Understanding these differences can help inform your choices for hydration.

Quick Summary

This guide clarifies the distinction between still water and mineral water, explaining how sourcing and mineral content define each type. It details the different classifications of bottled water and examines the unique health benefits associated with naturally occurring minerals. The article provides a comprehensive overview of water types to help consumers make informed purchasing decisions based on their preferences.

Key Points

Not Synonymous: All mineral water can be still, but not all still water is mineral water; 'still' describes texture, while 'mineral' describes composition and source.
Defined by Source: Mineral water must come from a protected underground source and contain a minimum of 250 ppm of naturally occurring dissolved solids.
Absence of Carbonation: Still water is simply any non-carbonated water, which can include tap, spring, purified, or mineral water.
Mineral Content Matters: Still mineral water contains natural minerals like calcium and magnesium, which offer potential health benefits not present in purified or distilled still water.
Labeling is Key: Check the bottle's label for terms like 'natural mineral water' to ensure the product meets the specific regulatory requirements for mineral content.

Unpacking the Definitions: Still Water vs. Mineral Water

To understand the relationship between still water and mineral water, it is crucial to first define each term independently. Still water is simply non-carbonated, meaning it lacks the dissolved carbon dioxide that gives sparkling water its bubbles and effervescence. This broad category can include everything from purified tap water to spring water and, importantly, some mineral waters. Stillness refers only to the absence of carbonation, not to its mineral composition or origin.

Mineral water, on the other hand, is defined by its source and mineral content. It must originate from a protected underground source and contain a stable level of naturally occurring minerals and trace elements. Regulations, such as those from the FDA, mandate a minimum concentration of dissolved solids for water to be labeled as 'mineral water'. A key difference is that no minerals can be added to the water to meet this requirement; they must be present naturally.

The Overlap: When Still Water is also Mineral Water

An important concept to grasp is that the terms are not mutually exclusive. A bottled water can be both still and mineral, provided it meets the criteria for both. This occurs when water from a mineral-rich underground source is bottled without any added carbonation. The label will typically state 'natural still mineral water' to reflect both properties. However, a bottle of 'purified still water' that has undergone processes like reverse osmosis to remove impurities and minerals is distinctly not mineral water, even though it is still.

Comparing Different Types of Water

To better illustrate the distinctions, here is a comparison table of common water types:


Feature	Mineral Water	Purified Water	Spring Water	Tap Water (Municipal)
Source	Protected underground aquifer	Any source (municipal, well, etc.)	Natural spring	Local water supply
Mineral Content	Naturally high and consistent	Minerals removed; can be added back	Can contain naturally occurring minerals	Varies by location; minerals added or removed
Carbonation	Can be still or sparkling	Almost always still	Almost always still	Still, not carbonated
Treatment	Minimal treatment allowed	Extensive filtration (e.g., reverse osmosis)	Minimal filtration to remove contaminants	Varies by municipality; chlorinated/filtered

The Health Implications of Mineral Content

The naturally occurring minerals in mineral water, such as calcium and magnesium, are linked to various health benefits. For instance, calcium-rich varieties can support bone density, while magnesium is associated with improved cardiovascular health and glucose regulation. While the mineral content in still mineral water can vary greatly depending on its geographic source, these natural additions distinguish it from highly processed or purified still water, which often lack these beneficial elements. The absence of carbonation also makes still mineral water a gentle and easy-to-digest option, suitable for those with sensitive stomachs who might experience discomfort from carbonation.

Making Informed Choices for Hydration

When selecting a bottle of water, a quick look at the label is all that is needed to determine its true nature. The term 'natural mineral water' guarantees that the water contains a certain level of natural minerals from an underground source. If the label simply says 'still water' or 'purified water,' it is not considered mineral water under regulatory standards. The choice between them often comes down to a balance of taste preference, perceived health benefits, cost, and environmental impact.

For everyday hydration, filtered tap water or purified still water is a cost-effective and environmentally conscious option. For those seeking the potential health benefits of specific minerals or a particular taste profile, still mineral water offers a more premium alternative. Many consumers also enjoy the clean, neutral taste of still water and find it the most versatile for drinking and cooking. For more detailed information on the composition of various water sources, you can consult studies like those published by the National Library of Medicine.

Conclusion: The Final Word on Still and Mineral Water

In summary, still water and mineral water are not synonymous, though they can overlap. Still water refers solely to the absence of carbonation, a descriptor for its texture, while mineral water is defined by its natural mineral content and origin. A bottle of mineral water may be still or sparkling, but a bottle of still water is only mineral if it meets the specific criteria for naturally occurring dissolved solids. By understanding these key differences, consumers can make more informed decisions about the type of water they choose to drink for their hydration and wellness needs.

Frequently Asked Questions

The primary difference is their definition: still water refers to a lack of carbonation, while mineral water is defined by its source and naturally occurring mineral content. Some mineral waters are still, but not all still waters have the mineral content required to be classified as mineral water.

No, purified still water cannot be called mineral water. Purified water undergoes extensive treatment, such as reverse osmosis, that removes minerals. Mineral water must contain naturally occurring minerals from its original underground source.

Yes, still water is crucial for basic hydration and bodily functions. If it is still mineral water, it provides additional benefits from its naturally occurring minerals. Even filtered tap or purified still water is essential for health, as stated in health recommendations.

You can tell by reading the label. If it is mineral water, the bottle will be clearly labeled as 'Natural Mineral Water,' often stating the source and a mineral analysis. A bottle simply labeled 'still drinking water' or 'purified water' is not mineral water.

Yes, for hydration purposes, they are equally healthy. The only significant difference is the presence of carbonation in sparkling mineral water, which can cause bloating or gas in some individuals. The natural mineral content and hydration properties are the same.

Generally, yes. Because it must be sourced from a specific, protected underground source and contains naturally occurring minerals, mineral water is often marketed as a premium product and typically costs more than purified or tap-sourced still water.

This depends on personal preference, health goals, and local tap water quality. Still mineral water provides a consistent mineral profile and purity from its source. However, for most people, high-quality filtered tap water is a practical, cost-effective, and environmentally friendly choice for daily hydration.