Though it can sometimes be hard to fathom, your adorable domesticated kitty cat is descended from ancient desert-dwelling African wildcats. This hearty heritage has led some to suggest that cats are better adapted to surviving on less water than dogs or other domesticated species.
While it’s true that cats tend to require less water than dogs on a per pound basis and may also better tolerate mild cases of dehydration, it’s unsafe to assume they can exist under the same conditions as their ancestors.
Though they are both part of the same family tree, the lifestyle and diet of ancestral wildcats is very different from today’s domestic cats. Wildcats obtain most of their water from the prey that they eat and maintain high levels of activity. Meanwhile, many domestic cats eat kibble containing little moisture and are often quite sedentary. This may make domestic cats more prone to dehydration, which can lead to or exacerbate certain health conditions.
But how much water do cats actually need and how long can a cat go without water? Continue reading to find out everything you need to know to keep your cat safe and well-hydrated.
Why Cats Need Water
All life on earth needs water to survive, and cats are no exception. Roughly 60 percent of your cat’s body is made up of water (1), which sustains many of your cat’s basic bodily functions. Without it, cats would be unable to swallow and digest food. Water is also the main component of blood which is necessary to deliver oxygen and nutrients throughout the body. And water plays a key role in producing urine, which helps to rid the body of waste products.
How much water do cats need? An average-sized healthy adult cat needs about 7 to 8 ounces of water per day. However, how much water your cat actually needs to drink each day can vary depending on the moisture content of their diet. Dry food contains only about 10 percent water, so if you’re feeding your cat a kibble-only diet, you’d want to make sure your pet is drinking plenty of water. Wet or canned food contains 75 percent water, so it would be normal for cats eating this type of diet to drink a bit less.
Certain health complications could affect how much water your cat requires, as well. For example, cats with kidney disease cannot produce concentrated urine. That means they lose more water when they pee, so they have to drink a lot more water than a healthy cat in order to stay hydrated. Cats with diabetes and urinary disorders should also drink more water.
How Long Can a Cat Go Without Water?
Cats should always have plenty of fresh water available to them. However, since feline renal systems are quite efficient when it comes to producing concentrated urine, cats may be able to tolerate short periods without water better than other animals, provided they are healthy. So if you forget to refill your cat’s empty water bowl for a few hours, this will likely not cause an issue. But it’s not a good idea to make it a habit.
Generally speaking, if your cat eats only kibble and you haven’t observed them drinking water for 24 hours or longer, that’s cause for concern and merits an immediate trip to your veterinary clinic.
However, if your cat is on a wet food only diet and they are still eating normally, don’t panic if you don’t see them drinking water for a day or two. Remember that wet food is made up of mostly water, which makes it easier for cats to stay hydrated. Now, if you noticed that same cat wasn’t eating or drinking for a full day, that would be concerning. If such a pattern continued for three or more days, severe and potentially life-threatening dehydration could result.
If your cat has advanced kidney disease, diabetes, or is on a diuretic for the management of congestive heart failure, dehydration can develop much faster and can become potentially severe within a day. Cats that are experiencing vomiting and diarrhea can also become dehydrated rapidly.
Signs of Dehydration in Cats
It is important for pet parents to become familiar with the signs of dehydration in cats, especially if their cat has a chronic illness like kidney failure. The following are signs of dehydration:
- Dry or sticky gums
- Thick, stringy saliva
- Sunken eyes
- Skin becomes less elastic
- Rapid heart rate
If any of the above symptoms occur in your cat, consult with your veterinarian immediately.
How to Get Cats to Drink More Water
Healthy cats will typically self-regulate their water consumption and drink as much as their body needs. However, cats that are chronically under-hydrated may be more prone to chronic kidney disease, obesity, idiopathic cystitis (abnormal urinary symptoms), or bladder stones. For this reason, pet parents may want to consider ways to increase their cats’ hydration at home.
Feeding cats all or mostly wet food can help your pet stay better hydrated than cats that are fed kibble-only diets. Kibble-eating cats are likely to drink more water, but studies indicate that the amount of water they consume may still fall short of the hydration contained in wet food-only diets (1).
But switching to wet food isn’t always a surefire solution to dehydration issues. Some cats may turn up their noses at a wet-food diet, especially if they were fed kibble their whole lives. In addition, some pet parents may consider wet food too expensive or inconvenient.
Another way to increase hydration for kibble-eating cats is to add water into their kibble. But determining how much your cat will tolerate is a delicate balance. For best results, always start by adding a small amount of water to your cat’s kibble to see how they react to it. If they still chow down, add a little more water to the kibble every time you feed them, as long as your cat continues to eat their food.
Some cats consider running water more appealing than a static water bowl, so you may be able to up your cat’s water intake with a cat drinking fountain or a dripping faucet. However, this is largely an individual preference so pet parents should experiment with different options to see what their cat likes most (2).
The location and type of water bowl you use may also play a part in how much your cat drinks. In a survey commissioned by the pet food company Royal Canin, results indicated that, on average, cats preferred drinking bowls with smaller diameters and liked to drink from bowls that were located in a room away from their food bowls (2).
Cat parents can also try adding small amounts of tuna water or chicken broth to their cat’s water to make it more aromatic and enticing.
All featured products are chosen at the discretion of the author. However, Great Pet Care may make a small affiliate commission if you click through and make a purchase.
Recently, Purina released a nutrient-enriched flavored water option for cats called Hydra Care. According to Purina’s testing results, offering this enhanced water in addition to regular water increased total water intake by 28 percent among cats in the study (3). The liver-flavored supplement is not just tastier than plain water, it’s designed to be thicker, too. That means cats consume a greater volume when they lap it up. If that sounds appealing, ask your veterinarian whether this supplement is appropriate for your cat.
For cats with urinary issues or abnormalities, such as a history of bladder stones or a tendency to urinate outside of the litter box due to idiopathic cystitis, a prescription urinary diet can help boost their hydration and prevent recurring issues. Prescription urinary diets, such as Royal Canin Urinary SO and Hill’s c/d diets, help to increase water intake by adding more sodium to the recipes, which makes cats more thirsty. These diets are not appropriate for cats with certain health issues such as heart disease and high blood pressure.
Ensuring your cat stays properly hydrated is critical to maintaining their overall health and wellness. But even if your pet requires some coaxing to meet their daily water requirements, these simple steps can help you get your cat to drink more water and stay hydrated. Just remember, if you are worried that your cat is not drinking enough water or is not adequately hydrated, make sure you speak with your veterinarian and take your cat in for an exam immediately if signs of dehydration are present.