Which type of water is the healthiest to drink? A comprehensive guide

The World Health Organization reports that about 73% of the world's population has access to safely managed drinking water, but quality can vary significantly. So, which type of water is the healthiest to drink for optimal wellness and safety? The answer is nuanced, depending on the source, processing method, and your personal health considerations.

Quick Summary

Comparing tap, filtered, mineral, alkaline, and distilled water shows a balance of purity, mineral content, and cost. Your healthiest option depends on your water source and personal needs.

Key Points

• Filtered tap water is often the best choice: It provides an excellent balance of purity, cost-effectiveness, and sustainability for most people.

• Mineral content varies and should be considered: Some waters, like mineral or remineralized filtered water, provide beneficial electrolytes, while distilled water lacks them entirely.

• Alkaline water benefits are debated: Claims about alkaline water neutralizing body acids or preventing disease are largely unproven, and the body's pH is tightly regulated regardless.

• Bottled water carries a significant environmental cost: It has a much larger carbon and plastic footprint compared to drinking from the tap, even when filtered.

• Know your source: Water quality differs greatly depending on its source and your location. Checking local Consumer Confidence Reports or testing well water is crucial for safety.

Understanding the Different Types of Drinking Water

Choosing the best water for your health can be confusing, given the array of options available. To make an informed decision, it is important to understand the characteristics, benefits, and potential drawbacks of each type.

Tap Water

Tap water, supplied by municipal systems, is a highly regulated and accessible option in many countries. The U.S. Environmental Protection Agency (EPA) sets strict standards for public drinking water, meaning it is often microbially safe. However, its quality can vary by location due to factors like aging infrastructure (leaching lead), agricultural runoff, or industrial pollutants. The taste is also dependent on the water source and treatment methods, such as chlorination, which some find unpleasant. Despite potential issues, tap water is the most cost-effective and environmentally friendly choice, especially when filtered. Regular monitoring through Consumer Confidence Reports (CCR), which public water systems must provide, can help you understand your local water quality.

Filtered Water

Filtered water is tap water that has been passed through a purification system to remove specific contaminants. Common filtration methods include activated carbon filters, which are effective at removing chlorine and improving taste, and reverse osmosis (RO) systems, which use a semipermeable membrane to remove a much wider range of contaminants, including heavy metals, chemicals, and bacteria.

• Pros: Improves taste and odor, removes specific contaminants of concern, and is more environmentally friendly than bottled water.
• Cons: Upfront cost for the system, ongoing cost of filter replacements, and RO can strip water of beneficial minerals. Some people find RO water tastes "flat" due to the lack of minerals.

Remineralized Reverse Osmosis (RO) Water

For those who use RO filtration but want to reintroduce healthy minerals, remineralization is an option. Special alkaline mineral filters can be added to an RO system to increase the pH and add back essential minerals like calcium, magnesium, and potassium. This provides the high purity of RO with the added health benefits and improved taste of mineralized water.

Mineral Water

Mineral water is bottled at the source from geologically protected underground mineral springs and contains a consistent amount of naturally occurring minerals. By FDA standards in the U.S., it must contain at least 250 parts per million of total dissolved solids. These minerals, including magnesium and calcium, can offer health benefits like improved bone and heart health.

• Pros: Naturally rich in beneficial minerals and often has a unique, pleasant taste.
• Cons: Expensive and comes with a significant environmental footprint due to bottling and transportation.

Spring Water

Spring water is sourced from an underground aquifer that naturally flows to the surface. It undergoes natural filtration through layers of rock and soil. While it contains minerals, the amount is not regulated or consistent like in mineral water, so it can vary between sources. It is valued for its natural purity and refreshing taste.

Alkaline Water

Alkaline water has a higher pH level (typically 8 or 9) than neutral tap water (pH 7). It contains alkaline minerals like calcium and magnesium. While proponents suggest it can neutralize body acidity, improve hydration, and offer other benefits, many health professionals state that strong scientific evidence is lacking and advise caution. The body's internal systems, like the kidneys and lungs, tightly regulate blood pH regardless of the water consumed. Alkaline water can be naturally sourced or artificially produced using an ionizer.

Distilled Water

Distilled water is created by boiling water into steam and then condensing the steam back into a sterile liquid. This process removes all contaminants, including minerals, salts, and electrolytes, making it extremely pure. While safe for short-term use, long-term consumption is not recommended because it can lead to mineral deficiencies and has a flat taste. It is primarily used for medical equipment, appliances, or in laboratory settings.

Comparison of Major Water Types

Feature	Tap Water (Unfiltered)	Filtered Tap Water (e.g., Carbon)	Filtered Tap Water (Reverse Osmosis)	Mineral Water	Distilled Water
Purity	Variable, regulated by EPA in the US	Improves purity by removing chemicals & some metals	Very high, removes most contaminants & solids	High, naturally pure at source	Extremely high, free of all minerals & solids
Mineral Content	Varies by location	Variable, depending on original source	None (unless remineralized)	High and consistent	None
Taste	Variable, can have chlorine aftertaste	Improved taste and odor	Can be described as flat	Distinctive, due to minerals	Bland and flat
Cost	Lowest	Low to moderate (initial filter cost, replacement)	Higher (system installation, filter replacement)	Highest	Moderate (home distiller) to low (purchase)
Environmental Impact	Lowest	Low	Moderate (energy use, water waste for some systems)	Highest (plastic bottles, transport)	Moderate (energy for distillation)

Making the Healthiest Choice for You

Determining the absolute healthiest water depends on your specific needs, location, and budget. However, for most people, the ideal choice balances safety, mineral content, sustainability, and cost.

• Prioritize Safety: First and foremost, ensure your water is free from harmful bacteria and heavy metals. For those relying on public water systems, reviewing your annual Consumer Confidence Report can provide peace of mind. For well water, regular testing is crucial. If safety is a concern, a certified filtration system is a worthwhile investment.
• Consider Filtration: For a great balance of purity and cost, a home filtration system is an excellent option. Basic carbon filters improve taste, while reverse osmosis provides more comprehensive purification. If using RO, consider a remineralization cartridge to add back beneficial electrolytes and improve flavor. Learn more about choosing the right system at the Consumer Reports Water Filter Buying Guide.
• Balance Minerals and Cost: While mineral water can be beneficial, it is expensive and environmentally damaging. Filtered tap water, especially when remineralized, offers a similar mineral profile at a fraction of the cost and with less waste. Remember that most essential minerals are acquired through a balanced diet, not primarily through water consumption.
• Think Sustainably: Choosing filtered tap water over bottled water drastically reduces your environmental footprint. The production and transport of plastic bottles have a high carbon footprint, and billions of bottles contribute to landfill and ocean waste each year.

Conclusion: Finding the Best Water for Your Health

Ultimately, the healthiest type of water to drink for most people is high-quality, filtered tap water. This provides a balance of safety, taste, and sustainability that other options often lack. While mineral water offers a rich mineral profile and alkaline water has a higher pH, their benefits can often be replicated more affordably and ethically through home filtration, particularly with remineralization. Distilled water is too demineralized for regular, long-term consumption. The key is to assess your local tap water quality, address any specific contaminants with a certified filter, and drink plenty of it to stay properly hydrated. Safe, clean, and accessible water is the most important factor, and for most, filtered tap water is the best answer.

Frequently Asked Questions

Is bottled water healthier than tap water?

Not necessarily. While bottled water is often marketed as purer, it is not subject to the same stringent regulations as municipal tap water in many places. Some bottled water is simply filtered tap water, and the plastic can introduce microplastics. Filtered tap water is often a safer, more economical, and more sustainable option.

Does reverse osmosis water cause mineral deficiency?

Reverse osmosis removes up to 99.9% of total dissolved solids, including beneficial minerals like calcium and magnesium. While diet is the primary source of these minerals, drinking demineralized RO water can contribute to deficiencies if your diet is poor. This can be addressed by using a remineralizing filter.

Can alkaline water actually improve my health?

Scientific evidence supporting the health claims of alkaline water is limited and inconclusive. Your body's natural homeostatic mechanisms, regulated by the kidneys and lungs, maintain a very narrow pH range in your blood. Any temporary pH change from drinking alkaline water is quickly corrected.

What is the downside of drinking distilled water?

The main downside is the complete lack of minerals. While distilled water is extremely pure, it can taste bland and, over time, potentially lead to mineral deficiencies if not offset by a balanced diet. It is better suited for specific medical or appliance uses.

How can I tell if my tap water is safe?

For those on a public water system, you can review the annual Consumer Confidence Report (CCR) from your local water utility. If you have well water or are concerned about specific contaminants like lead from old pipes, consider using an EPA-certified lab to test your water.

What type of filter is best for home use?

The best filter depends on your water source and what contaminants you need to remove. Activated carbon filters are good for improving taste and removing chlorine. Reverse osmosis offers more thorough purification. Knowing your specific water quality concerns will help you choose the right system.

Is drinking water from a natural spring safe?

Natural spring water can be very pure, but it is not guaranteed to be free of contaminants. It is not recommended to drink untreated water directly from a spring as it could contain harmful microorganisms. Bottled spring water, however, is regulated and should be safe.