How To Fatten Up A Cat? [ Step By Step Guide ]

Are you going nuts thinking why your cat is underweight even if it is munching on plenty of food all day long? Or have you caught the sight of any malnourished and lean stray cat? Are you worried about how to bring in some health in your cats?

Well, there are many ways to put some fat in the cats, but first, we need to understand the reason behind the weightlessness, and then only the correct amount and type of nutrition can be provided. Let us take a look at all the concerns in detail.

How to fatten up a cat? A Step By Step Guide

After covering all the areas that could cause weightlessness in cats, we can look at the factors that help in weight increment.

Use kitten canned food

Kittens require more nutrients for faster growth and development. So kitten canned foods contain higher levels of protein and fat per gram than the canned food made for adults. This way, the malnourished cat gets more essentialities, including additional amounts of amino acids and fatty acids, which help bring strength to their growing muscles and organs. This way, the cat gains a healthy weight.

Prefer canned and wet food over dry food

Cats who have a loss of appetite due to tastelessness caused by some kind of irritation inside their mouth or infection in the internal organs find it difficult to swallow dry food and, as a result, lose the drive to eat. Well, canned and wet cat food is much richer in proteins and lower in carbs, and this provides an easy and better diet for the cats.

Increase the food amount gradually

Stuffing up your cat the next day, you start noticing an underweight cat is not a solution, which can cause the cat to get even sicker. Instead, you must consider incrementing the quantity of its food slowly. The actual way to do that is to divide the day’s diet into small parts and give them little amounts. Gradually decrease the sessions and increase the amount.

Supplement fish oil

Fish oil is beneficial to an undernourished cat in many ways. It works excellently on bringing up the levels of the calorie content in the cat’s body and helps build up more flesh in them. It also helps in enhancing the health and shine of the cat’s fur and eliminates the dull look. It is a good source of fatty acids and omega.

Offer healthy homemade treats and prices

There are so many foods that you can prepare at home according to your cat’s liking and accurate to the vet’s suggestions. Little treats of boiled chicken or egg or raw salmon can help majorly in bringing up a cat’s weight.

But it would be ideal if you remembered that these foods should be boiled or raw and not fried, with no added spices. If your cat enjoys these treats, you can start giving them snacks between meals. To bring this to your cat’s liking, you can offer these treats as a prize to achieve certain goals.

Make the food more attractive

Sometimes cats are simply unwilling to eat bland food and can make a lot of fuss about it. In that case, it becomes difficult to put in some essential calories in their body. Then you have to either find a way to sneak in some more calories in the cat’s food or simply make the food more interesting.

You can change the shape or color of the food and bring variation in temperature of different food items. But avoid serving too hot as they might burn themselves, and all your efforts will go to waste as your cat will shut down the eating again for the next few days.

Change the type of meat frequently and try serving them in bowls of their likings. This way, cats will get more inclined and eager for the next meal.

Have more than one option

Just like us human beings, cats can’t have the same food every day, and it does not fulfill giving the cat all types of nutrients, and also, the cat loses its urge to eat. You can try offering different kinds of food on regulation and see which one is your cat’s favorite.

It helps particularly in the case of cats who lose appetite and the urge to eat.

Keep an eye on intolerances and dislikes

You might be giving the best on your part, but you never know which formulated food can bring down the weight in cats. This problem may arise even if there is progress in the cat’s appetite. Initially, the cat enjoyed the new formulated food and was able to digest it easily, but now it is becoming the cause of weight loss and making your cat feel unwell.

The signs of gas, smelly feces, loose motion, vomit, diarrhea, loss of appetite are clear and prompt to stop that formula immediately and switch to a healthier and lighter version of the food.

Ruling out the possibilities of weightlessness

Many reasons can justify why a cat is underweight. To find out the actual medical cause behind your cat’s low weight, you can go to the vet. The most common ones are:

Dental problems

Sometimes pain in the teeth due to an injury or some infection inside the mouth makes the eating unpleasant. In that case, the cat avoids using its mouth much and does not eat, which leaves it malnourished.


Intestinal parasites are a common cause of being underweight in cats. The parasites take up all the necessary nutrients from the host’s body and do not allow them to grow properly.

Food allergies or sensitivities

Some food adds to the list of cats some of the dislikes. Those foods make the cat unwell and thus are not ideal for them. So this adds to the reduction of weight in cats.


There is no doubt that if the animal has any sort of infection and is unwell, it will never be food-driven, and the lack of nutrition will cause its weightlessness.


Just like human beings, cats also undergo hyperthyroidism, and it causes cats to lose weight rapidly. In addition to this, cat foods contain a chemical from soy-rich protein and fasten up weight loss.

Inflammatory bowel disease

Pain and discomfort caused due to inflammatory bowel disease can be significant reasons the cat is unwilling to eat and loses weight. Anxiety, sensitivities, and intolerances follow this.

All these problems can be diagnosed after the vets collect the urine and feces samples for the tests. Once the cause is diagnosed, it will be easier to provide better and specific nutrition. Ensure that you follow the exact instructions given by the vet and provide the right quantity needed.

Some products that help cats to gain weight

Merrick backcountry raw-infused game bird recipe

It is rich in protein and has infused calories in frozen raw meat for the real flesh of duck and quail.

Nature’s variety instinct original grain-free chicken cat food

It is a high-calorie wet formulated canned food made from 95 percent of animal protein from the meat of turkey chicken liver, which is grain-free and contains no added preservatives.

Nulo freestyle grain-free chicken and cod recipe for cat

A good combination of 40 percent of loaded protein and 20 percent fat. It is grain-free and easy to digest, and the main highlights are the natural flavors of chicken and cod.

Solid gold indigo moon high-protein in cat food

It is loaded with wholesome and natural ingredients like Alaskan Pollock and serves with more than 450 calories per cup. It helps to enhance the lost appetite.

Merrick purrfect bistro grain-free canned food

Completely free from additive chemicals and grains like corn, and is rich in essential fats and proteins, which help in the gradual increment in weight of cats.


What should I feed my underweight cat?

Kitten canned food can help greatly in bringing up the weight in your cat. If you want to increase the weight, then the food you are feeding your cat must be 30 percent of protein and 20 percent of fat if it has a dry consistency.

Wet cat foods are already nutritious and just require 7 percent of proteins and 5 percent of fat content. You can also give your cat high-calorie cat food, which is primarily made of 100 percent animal sources.

How can I fatten up my older cat?

Older cats can make a great fuss and often get picky about their food. So it would be effective if you tried to give it various options to choose from and make sure to provide it with what it prefers. Try to ensure the cat gets what is essential for its growth.

Try to preheat the food a little bit and give it in small but frequent quantities. Try to reduce stress and anxiety and give them snacks between meals. Canned kitten food rich in animal sources and natural meat flavors enhances the appetite and urge to eat food. Ensure to consult with your vet before changing your cat’s diet plan.


If your cat is underweight, there is no need to freak out. Take things calmly and visit a vet, follow its recommendations and give your cat what is best for it. After trying all the above-suggested variations, just wait for some time for better results.

If any symptoms come out of the way, immediately stop the food item causing the ailment and visit the vet directly. With some observation, dedication, and proper consultation, your cat will healthily gain weight and will all be in shape and in good health. You will have a robust and energetic cat within no time.

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