We’ve all seen the posters of the chubby kitty in the veterinarian’s office, and as pet parents, we’ve been warned about the dangers of feline obesity. According to a 2018 survey from the Association for Pet Obesity Prevention, about 60 percent of cats in the U.S. are overweight or obese (1). But having an underweight cat is just as problematic, and it isn’t always linked to a serious underlying condition like cancer or diabetes. Just like humans, cats can lose interest in their food for a variety of reasons, including stress and anxiety, or simply old age

Body condition score charts can help to evaluate an ideal shape for your cat. If you can easily see and feel your cat’s ribs and he has an obvious waist, these are good indicators that he might be malnourished or below a healthy weight. Changes to your cat’s skin and coat quality can also be indicators of poor nutrition. 

A cat’s diet is incredibly important to his overall health and wellbeing. An average healthy adult cat weighing 11 pounds should consume around 250 to 290 calories per day (2). If your cat’s body condition is less than ideal (too thin), he will have higher requirements. 

If your cat is underweight, finding the right food to help him safely gain weight is vital to avoid further health issues. That’s why we’ve rounded up the best cat foods for weight gain and everything you need to know to make the right choice for your pet. Always consult your veterinarian before starting your cat on any new diet.

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Best Cat Food for Weight Gain: 7 Enticing Options

Best Wet Cat Food for Weight Gain

Our pick: Smalls Human-Grade Cat Food

Smalls human grade cat food

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Smalls specializes in fresh, human-grade (aka high-quality) cat food, like 90 percent lean ground beef with 10 percent heart and liver in their cow recipe. Using all-natural proteins to feed your “obligate carnivores,” Smalls delivers grain-free, meat-packed nutrition in tempting flavors and textures that will entice picky eaters. While it’s not technically “high-calorie,” this high-protein wet cat food is calorically dense because it doesn’t contain fillers.


  • Three flavors (chicken, turkey, and beef) and two textures (ground and smooth) are sure to result in a combination that will please your pet 
  • Ingredients are USDA certified, humanely harvested, and sustainably sourced
  • No preservatives, artificial flavors, colors, or other additives

Things to Consider

  • After a trial box (11.5 ounces of five varieties), Smalls is subscription-based plan that ships every 4 weeks

Best Canned Cat Food for Weight Gain

Our pick: Instinct Original Grain-Free Pate

Instinct Original Grain-Free Pate Real Chicken Recipe Wet Canned Cat Food

Instinct’s cage-free chicken pate is another great wet food pick. Packed with 95 percent animal protein (excluding the broth), this recipe is also grain-free and rounded out with wholesome fruits and veggies.


  • Also available in rabbit, duck and salmon flavors, for cats who are not crazed about chicken
  • Made without grain, corn, wheat, soy, potato, gums, artificial colors, flavors, or preservatives
  • Contains omega-fatty acids from flaxseed and fish oil for skin and coat health 

Things to Consider

  • Two 3-ounce cans or one 5.5-ounce can is recommended per day, per 6 to 8 lbs. of body weight (possibly more for added weight gain)
  • Some reviewers (and their cats) were turned off by the soupy texture

Best Dry Cat Food for Weight Gain

Our pick: Blue Buffalo Wilderness High Protein Dry Cat Food

Blue Buffalo Wilderness High Protein Dry Cat Food

Protein-rich flavors like chicken, duck, and salmon help with lean muscle mass development, while omega-3 and omega-6 fatty acids protect a cat’s skin and coat. Healthy carbs like sweet potatoes help sustain kitty’s energy levels and are a great substitute for grains or fillers, which are not used in Blue Buffalo’s recipes. 


  • The food contains 40 percent protein from real chicken, with 443 calories per cup
  • The brand’s exclusive “LifeSource Bits” are a combination of antioxidants, vitamins, and minerals, developed by animal nutritionists and holistic veterinarians, including blueberries and cranberries

Things to Consider

  • Available in a variety of sizes, including 2.5-, 6- and 12-lb. bags
  • Some reviewers noted that the kibble size has increased
  • This food has mostly rave reviews, but some pet parents claim their cat developed urinary or kidney issues after eating it

Best Prescription Cat Food for Weight Gain

Our pick: Royal Canin Recovery

Royal Canin Veterinary Diet Recovery RS Canned Dog & Cat Food

Will wet food help my cat gain weight? It certainly can. Formulated by veterinary specialists, this high-protein blend is intended to pack on the pounds. It’s suitable for hospitalized pets, those recovering from an injury or illness, and picky eaters who have lost interest in food. Made with chicken and chicken liver, this pet food gains high marks because of its calorically dense recipe and its mousse-like texture, which is easy to chew and swallow. 


  • High-fat formula ensures a little food goes a long way for pets without an appetite
  • Suitable for both cats and dogs 

Things to Consider

  • This is a prescription food that requires a script from your vet
  • This critical-care recipe isn’t cheap, costing about $2.50 per 5.1-ounce can
  • Some reviewers noted that the can size is slightly smaller but costs the same

Best Kitten Food for Weight Gain

Our pick: Wellness Core Natural Grain-Free Kitten Food

Wellness CORE Natural Grain Free Turkey & Chicken Liver Pate Canned Kitten Food

This protein-dense kitten food will help your cat gain weight, no matter the age. Available in multiple flavors, such as turkey and chicken liver or whitefish, salmon and herring, these cans serve up nutrients as well as variety in a highly digestible and moisture-rich formula. 


  • Soft texture makes it easy on senior cats and those with dental problems
  • A substantial 12 percent crude protein and 38 percent of overall calories from protein
  • No artificial flavors, colors, preservatives or carrageenan

Things to Consider

  • Its price point is on the higher side, at nearly $3 per 5.5-ounce can
  • While many reviewers say their kitties go crazy for this formula, some customers noted that their picky cats wouldn’t eat the food

Best Senior Cat Food for Weight Gain

Our pick: Hills Prescription Diet a/d Urgent Care

Hill's Prescription Diet a/d Urgent Care with Chicken Canned Dog & Cat Food

Extra energy and nutrients come in a silky cat food that’s highly digestible for senior kitties who need to preserve muscle mass and support their immune system. In addition to senior cats who need to be enticed to eat, this food is especially ideal for cats recovering from surgery, illness or injury. 


  • Formulated by veterinarians, with taste and palatability in mind
  • Its soft texture makes it adaptable to bowls, spoons, or syringes, depending on feeding method needed
  • Suitable for both cats and dogs

Things to Consider

  • This is a relatively pricey, prescription-only food

Best Value Cat Food for Weight Gain

Our pick: Purina One True Instinct High Protein Dry Cat Food

Purina ONE True Instinct Natural Grain-Free with Ocean Whitefish High Protein Dry Cat Food

Not every protein-rich diet needs to be from an expensive prescription cat food. For pet parents on a budget who just want to give their fur babies a weight boost, Purina offers a high-protein dry food, available in ocean whitefish or chicken recipes. Offering 356 calories per cup (for whitefish recipe), many cats will enjoy this textural combo of crunchy bites and tender, meaty morsels.


  • Contains 35 percent protein to promote muscle mass with no poultry byproduct meal, artificial colors, flavors, or preservatives
  • Omega-6 fatty acids to support skin and coat
  • A 3.2-lb. bag is less than $8; also available in 6.3- and 14.4-lb. bags

Things to Consider

  • Some customers noted their cats weren’t a fan of both textures

Cat Food for Weight Gain: Key Benefits

Cute cat looking to camera on patio outside

Food for underweight cats comes in a number of formulas and textures. Be sure to differentiate high-protein or high-calorie foods meant for daily consumption from supplements, like calorie-rich nutritional gels, intended for intermittent feeding.

Dr. Sarah Wooten, a small animal veterinarian based in Colorado, says that some cats might require a higher calorie diet and therefore could benefit from a high-calorie canned therapeutic food. Older cats, specifically, could take advantage of a highly digestible food rich in antioxidants, omega-3 and -6 fatty acids, guaranteed probiotics, and prebiotics. 

A safe and effective way to infuse some more calories into your adult cat’s diet is to feed a high-quality kitten food, which tends to be higher in calories. Cats diagnosed with specific health concerns, like early onset kidney disease, might be prescribed therapeutic food that targets these conditions directly. While more protein is great in general for pets to gain weight, a low-protein diet is recommended for cats with advanced kidney disease.

Food to Help a Cat Gain Weight: What to Look For

Cute cat looking up to camera

Dry kibble for an underweight pet should contain about 30 percent protein and 20 percent fat, while wet food should contain 7 percent protein and 5 percent fat or higher, according to PetCareRx. While both can be effective at providing your pet with increased calorie intake, wet food is usually easier to digest, especially for senior cats or kitties with dental disease. Plus, moist cat food can be microwaved to increase its aroma and lure hesitant eaters with smell.

When evaluating a cat food to help your pet gain a little extra fluff, be on the lookout for natural ingredients that emphasize protein and high-quality fats over grains and fillers. While some formulas have been developed by veterinarians for optimal weight gain, you need to make sure the food you purchase mentions a high-calorie or calorically dense diet, has plenty of protein, and perhaps above all, is a flavor and texture that your cat will actually eat and enjoy. 

How to Help a Cat Gain Weight: Tips and Advice

Cute cat looking concerned

Regardless of your choice of cat food, you and your veterinarian will need to determine underlying causes of your cat’s weight loss prior to adjusting his diet. Common and more serious causes of weight loss in cats can be overactive thyroid disorder, feline diabetes, intestinal parasites, dental problems, or FIV, which all require medication.

However, other common causes of weight loss in cats can be changes to their digestive system caused by age, the stress of a move, anxiety about feeding habits like bowl placement or crowding—even insufficient food due to another pet who might be stealing from their bowl. These causes for malnutrition can also be challenging but are resolvable once you identify the trigger. Consider creating a calmer environment for your cat to eat in, serving smaller meals throughout the day, or luring him by adding rotisserie chicken or canned tuna to his food.