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Are you worried about your skinny kitty? Here’s how to make your cat fat

It’s concerning to have an underweight kitty with protruding bones and non-existent fat pads. While you can find several feline weight-loss diets on the internet, there’s a scarcity of reliable information on how to make your cat fat. Many clueless cat parents randomly stuff their bony kitty with biscuits and high-fat snacks, only to watch their pet throwing up minutes later.

Anorexia or malnourishment, whether moderate or severe, has to be tackled with care as it comes with many serious health risks like gastrointestinal diseases and liver failure. A safe route to feline weight gain would be:

  1. Creating a calorie surplus feline diet with the right food
  2. Managing how much and how often your cat eats
  3. Monitoring progress and setbacks

How to get a cat fat with a calorie surplus diet

A calorie surplus diet doesn’t seem complicated—it’s all about feeding your kitty more calories than they burn, right? Well, it's not that simple. You must pay special attention to the source of calories in any high-calorie feline diet. Cats can get calories from three nutrients, outlined in the table below:


Calories per gram







Kitties are adept in processing calories from proteins and fats, not carbohydrates, because of their carnivorous biology. Cats have a shorter digestive tract than herbivores and omnivores, and eating anything other than meat can disrupt their metabolic speed and sensitise their tummy.

Bulking 101—Your kitty should be able to build muscles without gaining fat. Choose whole meat proteins. Don’t go for cheat meals packed with carbs and fats.

Source: Cédric VT

Irrespective of dietary goals, your kitty's food should respect their natural diet and contain:

  • Over 50% animal protein (as the primary source of calories)
  • Up to 20% animal fat (since fats are energy-dense, a small quantity works well as a secondary calorie source)
  • Between 0%–3% carbs

A malnourished kitty should eat high-protein wet food with real meat and fish every day to gain healthy weight. Avoid products with high fat or carb content (excess carbs are broken down into excess fat and stored in cells) as they add to unhealthy fat mass rather than bulking up muscles and bones.

How much and how often should skinny cats eat?

A healthy indoor cat needs 40–45 calories daily per kilo of their body weight. According to nutrition specialists, skinny cats should get 50–60 calories per day for every kilo of their total weight. 

That roughly translates to 280–400 calories a day, depending on your kitty’s size (i.e. an underweight Ragdoll or Maine Coon would need more food than a petite Siamese or a Sphynx). Since the calorie content of one wet food can sits between 70–100 calories, your kitty should consume four to six cans in a day to put on weight.

Don’t force your kitty to eat too much at a time. Spread out their daily intake in three to eight meals to avoid stressing their tiny tummies and triggering gastrointestinal episodes, such as gagging or throwing up undigested food, vomiting, and diarrhoea. Weight gain is a slow process and can take months, so be patient.

Cautionary tips for emaciated cats

If you have an extremely malnourished cat who hasn’t been eating for days, be wary of the risks of Refeeding Syndrome. An emaciated feline’s electrolyte levels may be off-balance, and overfeeding them can lead to liver or renal failure and hypocalcemia.

In such cases, talk to your vet about a suitable electrolyte supplementation plan (through oral or intravenous fluids) before reintroducing food. When your kitty is ready for food, give them tiny portions every few hours for the next ten days. Here’s a sample timeline:


Serving per meal
(per kilo of their weight)

Day 1–3

10–15 ml/g

Day 3–10

20–40 ml/g

Once your kitty’s vitals are normal and you get a green light from the vet, you can put them on a standard weight gain regimen.

It’s muscle time—Untamed helps cats build a healthy and toned physique

If you want your kitty to gain healthy body mass in a safe and steady manner, include Untamed in their diet. Our wet food is made with 60%–63% whole meat, offering ideal quantities of proteins and fats needed to develop muscles, joints, and ligaments. We make our gravy and jelly products with human-grade meat and natural ingredients that complement the feline digestive system and reduce the risk of gastrointestinal episodes.

Let the gains begin—Untamed kitties are driven by hardcore muscle power!

Image (c) Untamed

We have worked hard to create highly digestible meals that provide optimal nutrition to kitties. Our grain-free and sugar-free products offer:

  1. Quality proteins—We don't experiment with meat derivatives and plant proteins. It's human-grade meat and fish only. Our dishes have twice more protein than most cat food items in stores
  2. Safe formulas—Our recipes have been designed by vets to ensure they are free from all known allergens and contain all essential micronutrients like taurine and vitamin E. We also offer single-protein options, Chocka Chicken and Tuck-in Tuna, tailored for cats with severe food allergies or sensitivities
  3. Potent nutrients—Skinny cats fail to gain weight when they are on products with low nutrient potency (often resulting from extreme heat processing). Untamed meals are gently steamed to preserve the nutrient profile and bring out the taste and aroma of the meat
  4. Lip-smacking flavoursFussy kitties don’t stand a chance once introduced to our irresistible delicacies made from chicken, duck, ham, tuna, salmon, mackerel, sardine, and shrimp!

Take our TRY NOW quiz and tell us what your cat would fancy—we’ll deliver a trial pack to your doorstep at a sweet price!

Go-getter kitties need meals that promote endurance and flexibility—Untamed keeps them ever-ready for new adventures!

Image (c) Untamed

From lanky to lovely—Untamed supports effortless weight management at every age

Untamed formulas offer balanced nutrition to cats at every life stage. Whether you care for a developing kitten or an adult, our high-protein food is the answer! The soft and flaky meat in our dishes also agrees with senior felines with poor appetite or frequent digestion issues. While it’s normal for older cats to lose a few pounds, our nutrient-dense meals keep them vigorous and help them retain a decent body mass in their golden years.

Our happy clients have shared what happens when a kitty switches to regular Untamed meals. Here’s the timeline:

Period on Untamed

The Untamed effect

One week

  • Improved digestion
  • Kitty stays hydrated
  • A cleaner litter tray

Two months

  • Stronger bones, muscles, and teeth
  • Balanced appetite
  • No lethargy

Four months

Six months and up

Ordering Untamed is an easy drill!

Untamed is all about your convenience. Our perks include:

The best way to check out our products is to order a trial pack of our cat food online. Here’s how to get it within a day:

  1. Take our TRY NOW quiz 
  2. Select a meal plan
  3. Place the order

We are an eco-conscious brand with ethical production values. Our products are available in 100% recyclable aluminium cans. The meat and fish in our food come from cruelty-free and dolphin-safe sources.

Weight woes gone forever! Keep the scales balanced with Untamed!

Image (c) Untamed

Can dry food help with weight gain?

Many people recommend free-feeding calorie-dense dry food to skinny cats. Even though it can work, the results aren’t optimal. 

Biscuits have little meat and rely on addictive fat and taste enhancers to increase palatability. Most kibble products are also high in carbohydrates thanks to the following ingredients:

  • Grains like rice, oats, sweetcorn, etc. add to the volume of food but bring no real nutritional value
  • Legumes are a source of useless vegan proteins and come with too many carbs
  • Starch is often extracted from potatoes and peas and used as a binding agent
  • Sugar makes biscuits shiny

Kitties on biscuits gain body fat rather than muscles, which doesn’t contribute much to their health and wellness. To make matters worse, dry food increases the risk of diabetes, constipation, IBS, and bladder stones.

Even if a dry food product has high protein content, its bioavailability remains questionable. Kibbles usually contain a processed mix of proteins from meat derivatives, dairy, and vegetables. The feline digestive system cannot absorb these proteins effectively.

Check out the bioavailability of different protein sources used in cat food:

Protein source

Bioavailability rate (approximate values)



Chicken liver


Salmon, sardine, prawn, and tuna


Beef, pork, ham, or bacon


Soya chunks or soya milk


Processed proteins (including plant proteins and meat, fish, and insect meals)

Under 65%

How to fatten up a kitten—is kitten food necessary?

Some cat parents believe that kittens need to eat specialised food to reach the desired weight, but that is not true. Weaned off kittens need a high-protein diet based on whole meat. You should inspect the ingredients of a product sold as kitten food to verify their protein, fat, and carb contents.

Many kitten products, especially biscuits, are packed with more carbohydrates than proteins. They will fatten up your kitty without giving them proper muscle tone. A dry food diet can also turn kittens into kibble addicts, so they’ll struggle to accept wet food later in life.

A good strategy to beef up underweight kittens is to feed them small servings of wet food every 3–4 hours. Larger portions can cause diarrhoea, which can be super dangerous for younglings. Keep harmful food and snacks away from your kitten so that a nasty case of food poisoning doesn’t mar their development.

Is the wait to see some weight on your kitty getting uncomfortably long? It’s time for a thorough veterinary check-up.

Source: Anastasia/Anastasiya

What if my cat doesn’t gain weight?

If your kitty shows no improvement in their weight despite following a rigorous weight gain program for over a month, you must take them for a full veterinary evaluation. Unexplained weight loss is often associated with diabetes, hyperthyroidism, and intestinal cancer, which can be detected through bloodwork. Some of these conditions can be managed with prescription meds and a suitable diet.

Don’t cross the threshold—what makes a cat fat rather than fit

Once your kitty hits their ideal weight, ration their meals according to their current needs. Even a month of overfeeding can make cats fat. Both feline obesity and anorexia are two sides of the same coin—they impact your pet’s quality of life. For more information, check out our guides on: