How Much Water Does a Cat Need?

Water is essential to your cat’s health. Water is necessary for the cat's circulation, digestion, and waste removal. Dehydration in cats is typically caused by the cat not drinking enough water and it can lead to other severe medical concerns like kidney disease.

Why cats are more prone to dehydration?

Cats originated as desert animals obtaining most of their water supply from their prey. As desert dwellers, they are built to have a low thirst drive, which means that they don't feel the need to drink water very often. Instead, they get water from their food – small mammals, birds, and other creatures that they have hunted. The flesh of these prey contains about 70% water.

Our modern feline friends rarely hunt for food, and most are fed commercial cat food consisting of either dry cat food (kibble) or wet canned cat food. Dried cat food contains only 10% water whilst wet cat food contains around 80% water. Therefore, a cat fed on a diet of dried cat food will need to drink more water than one fed on canned wet food.  

How much water should a cat drink?

How much water a cat needs to drink daily really depends on the size (weight) and the diet that they are on. A good rule of thumb is a cat need about 60ml/kg per day of water. So, a 4kg cat will need approximately 240ml of water a day to ensure his body functions properly.

Let’s assume that this 4kg cat is being fed a wet cat food diet. He eats one can of cat food daily and a single can will supply the cat with 150g of wet cat food. Since wet cat food consists of 80% water, each 150g can of wet cat food provides the cat with 120g (120ml) of water. The cat would have consumed 120ml of water from his diet and that’s 50% of his daily water requirements. As such, he will only need to drink another 120ml of water, which is about ½ cup of water.

If this same cat has been fed a dry kibble diet that contains only 10% water, he will have to drink a lot more water, about 225ml of water to meet his daily water requirements.

Another plus point for wet cat food is - Water does not provide calories, therefore, wet food always has a lower energy density (calories) than dry food. So, for cat parents looking for better weight management cat food, here’s another reason to switch to wet. Here’s the Wellness CORE Signature Selects Paté Indoor Boneless Chicken Entrée Wet Cat Food, a wet cat food formulated for less active, indoor cats for better weight management.

The Sparkles Colours Chicken with Mackerel Topping Canned Wet Cat Food is also worth mentioning here as it has added gravy to improve flavour and increase the water content. This canned food contains 90% water. An excellent choice for cats that do not like to drink water.  

How to check for symptoms of dehydration in cats?

It is not always possible to measure the exact amount of water that your cat drank. Getting a water dispenser with graduated scale may help. The Stefanplast Chic Food & Water Dispenser For Cats & Dogs comes with a graduated scale to monitor your pet's consumption. 

Another way to check for signs of dehydration is to do the “pinch” test. To check the levels of hydration, pinch a small amount of skin on the back of your cat’s neck. If it springs back easily your cat is adequately hydrated. If it is slow to recede, suspect dehydration. This is like testing your own hydration level by squeezing the skin on the back of your hand.  

How to get my cat to drink more?

Here are some easy ways to encourage your cat to drink more water.

• If your cat is on a dry kibble diet, support your cat’s daily hydration goal by adding wet food to his dry food. Adding a wet food topper to their dry food increases their water intake while still providing them with the dry food they enjoy.
• Try a cat water fountain. Most cats love moving water and would prefer to drink from a fountain like this PETKIT Eversweet Solo Drinking Fountain for Cats & Dogs rather than a stagnant bowl of water. This drinking fountain also ensures that the water supplied to your cat passes through four filtration systems, removing unclean particles & excess oxygen.

• Change the water bowl location. This works if you suspect that your cat’s reluctance to drink is due to his water bowl being placed at the wrong location. A location with too much foot traffic or too close to his litter box. Consider moving it to a more secluded location or further away from the litter box.
• Change to a wider water bowl. Be aware that our cats’ whiskers are very sensitive to touch. Some cats do not like when their whiskers touch the edge of the bowl. If you are using a bowl for water, choose one that is non-slip and has a wider opening for easy licking. If your bowl doesn’t come with a non-slip bottom, do consider getting a non-slip mat like this Sapsal Soft Pet Mat For Cats & Dogs to prevent the bowl from slipping and toppling over.  

Other causes of dehydration

Dehydration could be caused by many different factors like:

• Diabetes
• Loss of fluid through diarrhoea and vomiting
• Cat fever
• Heatstroke and overheating

If you believe your cat is mildly dehydrated, encourage him to take in more water. If, however, the symptoms indicate severe dehydration, then it’s time for a vet visit. Fluids - electrolyte solution - may be administered either subcutaneously (under your cat’s skin) or intravenously (directly into your cat’s vein), depending on how dehydrated and sick your cat is. Keeping your cat properly hydrated may seem like a Herculean task, but with a few simple steps like adding wet cat food to dry cat food can help to keep your cat better hydrated.

KATHERINE KHOO

Katherine is a Pet Nutrition Specialist and GDP’s Pet Wellness Advisor. She is committed to helping pet owners make informed dietary and lifestyle choices in nurturing healthy pets. Katherine is also a practicing Nutritional Therapist (human nutrition) and has been helping hundreds of clients to heal naturally with nutrients.