Why Pure Distilled Water is Dangerous for Cats


Cats, like all animals, require water for hydration and health. Water plays an essential role in regulating body temperature, aiding digestion, eliminating waste, and transporting nutrients. Though cats can derive moisture from their food, they still need fresh clean water to drink every day. Distilled water lacks minerals and electrolytes and has an altered pH, which can pose potential problems for cats. This article will examine why cats should not drink distilled water as their primary water source, the importance of minerals and electrolytes, and the health issues that can arise.

What is Distilled Water?

Distilled water is water that has been boiled and condensed to remove impurities, minerals, and contaminants. The process of distillation involves heating water to the boiling point, capturing the resulting water vapor, and condensing the vapor back into liquid water in a separate container.

Water distillation works by taking advantage of the different boiling points of water and other substances. As water is heated, it evaporates, leaving behind substances that have higher boiling points. The water vapor is then cooled and condensed back into pure liquid water that is free of minerals, metals, salts and other impurities with higher boiling points.

According to the source What is Water Distillation?, the process of distillation “removes harmful contaminants from water that boil at a lower temperature than water”. Through repeated steps of evaporation, vapor collection and condensation, distilled water is purified and filtered from nearly all impurities.

Mineral Content

Distilled water lacks important minerals that cats need in their diet like calcium, magnesium, and sodium. Tap water and natural spring water contain trace amounts of these minerals, but the distillation process removes them from water (1). Cats require calcium and magnesium for strong bones and teeth, muscle function, and nerve transmission (2). Sodium helps regulate fluid balance and blood pressure. Without these essential minerals from their water source, cats can develop deficiencies over time leading to potential health issues.

The lack of minerals is one of the main reasons why drinking only distilled water long-term is not recommended for cats. While distilled water can be used short-term, cats should primarily drink tap or filtered water that retains trace minerals their bodies need.


Cats have a limited sense of taste compared to humans. According to research by Bartoshuk et al. [1], cats can detect the taste of water, which was previously thought to be tasteless to them. Cats have only around 470 taste buds compared to humans who have around 9,000. Their taste buds are concentrated on the tip of the tongue, allowing them to detect salty, sour, and bitter tastes.

However, cats have a difficult time tasting sweet flavors. Research shows cats are indifferent to sugars like sucrose that humans find very sweet [2]. This explains why most cats have no interest in sugary foods.

Pure distilled water lacks any minerals and has a flat, boring taste to cats. The lack of taste and odor makes it unappealing for feline drinkers. Cats strongly prefer water with some mineral content to enhance the flavor. The bland taste of distilled water does not entice cats to drink it.


Cats have a remarkable sense of smell, much more sensitive than humans. Their olfactory system has around 200 million smell receptors compared to only 5 million in humans (1). This allows cats to detect odors and chemicals in water that are undetectable to us.

One key difference with distilled water is that it lacks any discernible odor or taste. The distillation process removes minerals, chemicals, and contaminants that would normally give tap water a distinctive smell and flavor. According to Purina, cats can smell the chemicals in regular tap water that humans can’t detect (2).

But because distilled water is purified via distillation, it ends up being bland-tasting and odorless to cats. Without any familiar scents or tastes from minerals or chlorine, the distilled water likely smells “wrong” or unnatural to cats.

(1) https://www.quora.com/Do-cats-smell-or-otherwise-remotely-sense-water-What-makes-them-hesitate-near-a-bathtub-even-if-it-barely-has-any-water-in-it
(2) https://www.purina.co.uk/articles/cats/behaviour/common-questions/why-do-cats-hate-water

Acidic pH

Distilled water is slightly acidic, with a pH around 5.7-6.2, whereas the normal pH range for cats is 6.5-7.5[1]. Tap water and bottled water tend to be neutral or slightly basic. The acidity of distilled water comes from the water purification process which removes minerals that would normally buffer the pH[2]. While the acidity of distilled water is mild, over time it can upset the delicate pH balance in a cat’s body and potentially lead to negative health effects.

Kidney Function

Drinking only distilled water can put extra strain on a cat’s kidneys. Distilled water has no minerals and a pH around 5.8, making it more acidic than tap or mineral water. This lack of minerals and acidic pH forces a cat’s kidneys to work harder to balance electrolytes and the acid-base balance of its body. Over time, this strain can lead to kidney damage or exacerbate existing kidney disease (Source 1).

Normal, healthy kidneys filter waste from the blood while retaining needed electrolytes like sodium, potassium, and chloride. Drinking distilled water pulls minerals from the body during this filtration process. With fewer minerals to begin with, a cat’s kidneys must work harder to conserve what is left in the bloodstream. This makes the kidneys less efficient and can accelerate kidney problems in cats prone to kidney disease (Source 2).

For cats with chronic kidney disease, the kidneys have already lost some function. Providing distilled water forces compromised kidneys to work overtime, potentially leading to further kidney damage. For these cats especially, it is best to provide tap or filtered water with healthy mineral content to support kidney function.

Urinary Tract Health

Drinking distilled water long-term may put cats at higher risk for developing urinary tract stones and crystals. This is because distilled water lacks minerals like calcium and magnesium that help prevent the formation of these crystals (see Hard Water and Your Cat’s Urinary pH). Minerals in regular drinking water help keep a cat’s urine acidic, which prevents the buildup of crystals and stones. Distilled water does not contain these beneficial minerals, so over time it can make a cat’s urine more alkaline and prone to crystal formation.

According to veterinarians, most cats that form urinary tract crystals and stones do so because their urine is too alkaline rather than too acidic. The minerals in regular drinking water help maintain a healthy pH balance. Cats that drink primarily distilled water long-term are more at risk because they lack those helpful minerals in their diet (see Cat Water – Water for Cat). Providing cats with a mineral-rich water source can help lower their risk for developing urinary tract stones.


While distilled water is pure and free of contaminants, cats tend to not like the taste of it as much as regular drinking water. Cats have a much stronger sense of taste and smell compared to humans, and they can be put off by the lack of minerals and flat taste of distilled water [1]. This means that cats may drink less distilled water than regular water, risking mild dehydration if it’s the only water source available.

Dehydration can cause a range of issues in cats, including lethargy, dry mouth, sunken eyes, loss of skin elasticity, and constipation. In severe cases, it can lead to kidney problems, organ failure, seizures, and even death. That’s why it’s important for cat owners to monitor their cat’s water intake carefully if providing distilled water. Look for signs of dehydration, and consider switching back to regular drinking water if your cat doesn’t seem to be drinking enough distilled water.


In summary, cats should not drink distilled water as their sole water source because it lacks essential minerals, has an acidic pH, provides no taste or smell, and can lead to dehydration and urinary tract issues. Cats need minerals like calcium and magnesium in their water to support kidney function and urinary health. The ideal water for cats has a neutral pH, some taste and odor from minerals, and comes from safe, filtered sources like tap water passed through a filter or bottled spring water. To keep cats properly hydrated and healthy, provide them with mineral water instead of pure distilled water.

Scroll to Top