Copper water is an emerging trend that promotes the practice of storing drinking water in a copper container or copper water bottle.

While you may have just recently heard about this trend, it’s widely supported by Ayurveda, an Indian system of holistic medicine with ancient origins.

Still, you may wonder whether this practice is beneficial and safe or just another fad.

This article reviews the purported benefits and downsides of drinking copper water.

Copper water isn’t a beverage you’ll find in the nearest supermarket or health store. Rather, you have to make it by storing drinking water in a copper container.

Copper is a trace element, meaning that you only need minimal amounts of it.

It plays a key role in multiple essential body functions, such as the production of energy, connective tissues, and your brain’s chemical messaging system. It’s widely found in foods like shellfish, nuts, seeds, potatoes, whole grain products, dark chocolate, and organ meat (1).

Proponents of this practice state that storing water in copper containers allows the metal to infuse into the water, thus conferring benefits to the drinker.

Still, while both its deficiency and excess may be detrimental to your health, copper deficiency is uncommon (1).

For example, the standard American diet meets or exceeds copper’s Daily Value (DV) — the recommended amount of a nutrient you should consume per day — which is set at 0.9 mg (2).

Summary

Copper water refers to water that has been stored in a copper container, allowing it to become infused with the mineral. However, copper deficiency is rare, as your daily copper needs can easily be met through common foods.

Proponents claim that copper water offers multiple benefits, including better heart and brain health, a more robust immune system, and even weight loss, anti-aging, and tanning effects.

However, it’s unlikely that copper water provides these health effects.

Instead, these benefits may merely reflect copper’s roles and functions in your body, given that it’s involved in energy production, pigmentation, the development of brain and heart tissue, immune system function, and angiogenesis — the formation of new blood vessels (1).

Antibacterial effects

One of copper’s benefit appears to be backed by science — its antibacterial effect.

Both old and recent evidence suggests that copper may be used as a water purification or sterilization system, as ancient Ayurveda techniques recommended (3, 4).

This may be especially beneficial for the estimated 1 billion people who don’t have access to safe drinking water (5).

Contaminated water can contain considerable amounts of bacteria, including Vibrio cholerae, Shigella flexneri, Escherichia coli, and Salmonella typhimurium, that can cause diarrhea — one of the leading causes of death in developing countries (4, 5).

Fortunately, simply storing water in a copper pot or vessel may kill these harmful bacteria (5, 6, 7, 8).

The term “contact killing” is used to describe copper’s antibacterial effect. Researchers believe that exposure to the mineral causes extensive damage to the cell walls of bacteria, causing their death (9, 10).

Still, studies agree that water should be stored in the copper container for several hours before drinking it to ensure that the antibacterial effect has been successful.

Some research reported the antibacterial effect when storing the water overnight. In contrast, other studies suggest waiting 16–24 hours, or even up to 48 hours (5, 6, 7, 8).

This means that filling a pricey copper water bottle in the morning to stay hydrated throughout the day might not have much of a sterilizing effect.

Rather, keeping water in copper pots or jars for longer may be more useful.

Summary

Storing water in copper containers seems to have antibacterial properties capable of killing harmful bacteria. However, the water must be stored for several hours — possibly even days — for it to work.

Long-term exposure to high doses of copper may cause copper toxicity, which is characterized by nausea, vomiting, abdominal pain, and diarrhea. It may even lead to liver damage and kidney disease (1, 11).

One way you may develop copper toxicity is by consuming stagnant water that flows through copper-containing pipes, which allow for high quantities of copper to leach into the water (1).

The World Health Organization (WHO) recommends no more than 0.47 mg of copper per cup (2 mg per liter) of water. This ensures that the tolerable upper intake level of 10 mg per day won’t be exceeded (11).

When it comes to water stored in copper containers, even for periods of up to 16 hours, studies show that the amount of leached copper is well below WHO’s safety limits (5, 8).

Still, proponents of the trend suggest that you limit your copper water intake to 3 cups (710 mL) per day.

Summary

High copper intakes may lead to copper toxicity in the long run. However, the amount of copper that leaches into water stored in copper containers is below the safety limits.

Copper water is simply water that has been stored in a copper container. This allows for safe amounts of copper to leach into the water.

While most of the practice’s purported benefits aren’t backed by scientific studies, it exerts an antibacterial effect that may kill diarrhea-causing bacteria in contaminated water.

However, research suggests that for the leached copper to kill bacteria, the water must be stored in a copper vessel at least overnight or up to 48 hours.

This means that the best containers are most likely copper pots or jars rather than copper water bottles that are filled on the go.