What is the healthiest bottle of water to buy? An in-depth guide

October 8, 2025 •

4 min read

According to one recent study, a typical liter of bottled water can contain around 240,000 tiny pieces of plastic, prompting major concerns about purity and safety. For health-conscious consumers, knowing what is the healthiest bottle of water to buy involves looking beyond the label to understand sources and packaging.

Quick Summary

This guide examines the different types of bottled water, such as spring, mineral, purified, and alkaline. It addresses the health implications of packaging materials, including potential microplastic contamination and chemical leaching. Factors like mineral content and bottle material are weighed against safety and environmental impact.

Key Points

Check the Packaging: Avoid plastic bottles where possible due to risks of microplastic and chemical leaching, especially with heat exposure.
Choose Non-Reactive Materials: Opt for glass bottles or, for daily use, invest in a reusable stainless steel or borosilicate glass bottle to avoid contamination.
Understand Water Types: Know the difference between spring (natural minerals) and purified (highly filtered, low minerals) to match your preferences.
Evaluate Alkaline Water Claims: While potentially beneficial for some, the health claims of alkaline water are still under research and should not replace medical advice.
Filter Your Tap Water: The safest, most cost-effective, and most environmentally friendly option is often drinking filtered tap water from a reusable bottle.
Consider Mineral Content: While water provides only a small portion of daily mineral needs, spring and mineral water can offer a natural boost compared to purified options.

Decoding Your Hydration: A Guide to Bottled Water Choices

Your choice of bottled water goes beyond brand loyalty; it's a decision with implications for your health and the environment. While the primary goal is to stay hydrated, the source, purification process, and packaging all play a significant role in the overall quality and safety of what you drink. Understanding these differences is crucial for making an informed choice about what is the healthiest bottle of water to buy.

Comparing Different Types of Water

Bottled water is not a one-size-fits-all product. The source and treatment methods define its characteristics, from mineral content to purity.

Spring and Mineral Water

Source: Spring water comes from an underground formation from which water flows naturally to the surface. Mineral water originates from a protected underground mineral spring and must contain at least 250 parts per million of dissolved solids.
Health Benefits: These waters naturally contain electrolytes and essential minerals like calcium, magnesium, and potassium, which are absorbed from the rock and soil layers they pass through. This mineral content can contribute to daily nutritional intake.
Considerations: While naturally filtered, some spring and mineral waters may contain trace amounts of natural contaminants, so it's important to choose reputable brands. The mineral composition varies, giving each brand a unique taste profile.

Purified Water (RO, Distilled, etc.)

Source: Purified water can come from any source, including municipal tap water, but undergoes a controlled, multi-step filtration process.
Purification Methods: Common methods include distillation, reverse osmosis (RO), and deionization. This process removes harmful contaminants like chemicals, bacteria, and heavy metals, ensuring a very high level of purity.
Considerations: The purification process also strips away beneficial natural minerals. While this results in a very 'clean' taste, some argue it makes the water less healthy due to the lack of minerals. Some purified water brands add electrolytes back in for taste and rehydration purposes.

Alkaline Water

Source: Alkaline water has a higher pH level (typically 8 or above) than neutral tap water (pH 7). This can be achieved naturally by the water's mineral content or through an ionization process.
Potential Benefits: Advocates suggest that alkaline water can neutralize excess acid in the body, aid digestion, and boost hydration. Some studies also note it can reduce blood viscosity after exercise and may help with acid reflux symptoms.
Considerations: Research into the broader health benefits is still ongoing, and some claims need more evidence. Excessive intake of highly alkaline water could potentially disrupt the body's natural pH balance.

The Healthiest Packaging: Beyond the Plastic Bottle

While the water itself is a primary concern, the bottle it comes in is equally important due to potential chemical leaching and microplastic contamination.

Plastic Bottles: Convenience is their main draw, but plastic bottles, especially those made from PET, have raised significant health concerns. Studies confirm that chemicals like BPA and microplastics can leach into the water, particularly when the bottles are exposed to heat. A typical liter of bottled water can contain an average of 325 microplastic particles, and some studies have detected up to 10,000 pieces per liter in some brands.
Glass Bottles: Glass is considered one of the healthiest packaging options. It is inert, meaning it doesn't leach chemicals or microplastics into the water, preserving its purity and taste. The main drawbacks are that glass is heavier and more fragile than plastic.
Aluminum Cans: Aluminum cans are increasingly popular, offering a lightweight and infinitely recyclable alternative to plastic. However, it's worth noting that many cans are lined with epoxy resins containing bisphenol A (BPA), a known endocrine disruptor, though BPA-free options are available.
Reusable Bottles: For a sustainable and safe option, a high-quality reusable bottle is the best choice. Stainless steel is often called the 'gold standard' because it is durable, non-reactive, and easy to clean. Other safe materials include borosilicate glass, known for its shatter resistance. By using a reusable bottle filled with filtered tap water, you can ensure purity while minimizing both environmental impact and exposure to harmful packaging chemicals.

Comparison of Bottled Water Options


Feature	Spring Water	Mineral Water	Purified Water	Alkaline Water
Source	Natural underground springs	Protected underground mineral springs	Municipal tap or other sources	Various (natural minerals or ionization)
Mineral Content	Varies by source, naturally contains minerals	High mineral content (min. 250 ppm)	Low or no mineral content	Higher mineral content (calcium, magnesium)
Contaminant Removal	Naturally filtered, but may contain trace contaminants	Naturally filtered	Rigorously filtered (RO, distillation, UV)	Depends on purification method
Potential Health Benefit	Provides natural minerals & electrolytes	High mineral density, potential for bone health	Highest purity and safety assurance	Potential benefits for pH balance, digestion, hydration
Taste Profile	Unique taste based on mineral content	Distinctive mineral taste, can be salty	Neutral, consistent flavor	Smooth, potentially different taste
Cost	Mid-to-high price point	Generally expensive	Generally affordable	Often a premium, higher price

Conclusion: Making the Best Hydration Choice

Ultimately, the healthiest bottled water choice depends on your personal priorities. If you prefer naturally occurring minerals and a distinct taste, a reputable spring or mineral water brand in a non-plastic container is a great option. For those who prioritize purity above all, purified water is the safest bet, especially if sourced reliably. However, the best all-around health and environmental choice is often a high-quality reusable bottle made from stainless steel or glass, filled with filtered tap water. This approach minimizes your exposure to potentially harmful packaging chemicals and microplastics while significantly reducing your environmental footprint. Always consider the packaging as carefully as the water itself to ensure safe and healthy hydration.

Frequently Asked Questions

Studies have found microplastics in nearly all bottled water samples tested, regardless of the packaging material, although plastic bottles may contain higher levels.

Some studies suggest alkaline water may offer benefits like improved digestion or hydration, but the evidence is not conclusive and more research is needed to prove all health claims.

Spring water comes from a natural underground source and contains natural minerals. Mineral water must also come from a protected underground source and contain a minimum level of dissolved minerals (at least 250 parts per million).

Yes, chemicals like BPA and others can leach from plastic bottles into the water, particularly when the bottle is exposed to heat or reused over time.

Many experts consider food-grade stainless steel the healthiest choice for reusable bottles due to its durability, non-reactive properties, and resistance to chemical leaching.

The purification process, such as reverse osmosis, often removes most, if not all, of the naturally occurring minerals in water. Some companies add electrolytes back in for taste.

Aluminum cans are a better environmental choice than plastic due to high recyclability. However, some cans have liners containing BPA, so consumers should look for BPA-free lining options.