Cats sometimes struggle to gain weight due to illness or poor appetite. Choosing the right supplement helps support healthy weight gain.
A cat’s weight affects its health and happiness. Some cats eat less or burn calories too fast. Supplements add needed nutrients and calories to their diet. They help improve energy and muscle growth. Not all supplements work the same. Some focus on protein, others on vitamins or fats.
Knowing what your cat needs is key. This guide explains the best weight gain supplements for cats. It helps you pick safe and effective options. Feeding the right supplement can make your cat stronger and more active. Keeping your cat at a healthy weight helps prevent illness and improves life quality.
Our Top Picks
10 Best Weight Gain Supplements For Cats Of 2025
1. Under the Weather Ready Cal Powder for Cats | High-Calorie Weight Gainer & Appetite Stimulant | Cat Energy Booster Veterinarian-Approved Pet Supplement with Vitamins & Minerals | Chicken Flavor
- Brand: Under the Weather
- Manufacturer: undertheweatherpet
- Dimensions: Height: 4.24 Inches Width: 3.65 Inches Length: 3.57 Inches
Boost your cat’s energy with Under the Weather Ready Cal Powder. This high-calorie supplement helps your feline friend gain weight effectively. Packed with essential vitamins and minerals, it ensures your cat stays healthy. Approved by veterinarians, it’s a safe choice for your pet’s dietary needs. The delicious chicken flavor makes it irresistible to cats. Ideal for picky eaters or those recovering from illness.
Advantages
- Supports cats in gaining weight quickly and safely.
- Boosts appetite for cats that eat less or feel sick.
- Contains vitamins and minerals to improve overall health.
- Tastes like chicken, making it easy for cats to enjoy.
- Helps increase energy levels for active and playful pets.
Our Recommendations
My cat started eating more quickly after using this powder. The chicken flavor is something she likes a lot. I noticed her energy increased within a few days. The powder mixes easily with food, no mess at all. Vitamins and minerals seem to help her feel better. Vet approved, so I trust it is safe to use. This supplement helped my cat gain weight gently. Perfect for cats that need a little extra help.
2. Under The Weather Pet | Ready Cal for Cats 100cc | High Calorie Supplement | Cat Weight Gainer and High Calorie Booster | 10 Vitamins, 7 Minerals & Omega Fatty Acids (for Cats 100cc)
- Brand: Under the Weather
- Manufacturer: Under the Weather
- Color: Under The Weather
- Dimensions: Weight: 0.21875 pounds `
Under The Weather Pet Ready Cal for Cats offers a simple way to help your cat gain weight. Packed with 10 vitamins, 7 minerals, and omega fatty acids, it supports overall health. This high-calorie supplement boosts energy and helps cats recover faster. Gentle on the stomach, it suits cats with low appetite or illness. Easy to give and digest, it fits well into any cat care routine.
Advantages
- Supports healthy weight gain for cats needing extra nutrition.
- Contains 10 vitamins and 7 minerals for balanced health.
- Includes omega fatty acids to promote shiny fur and skin.
- Easy to feed, helping cats recover appetite quickly.
- Boosts energy levels in cats feeling weak or tired.
Our Recommendations
My cat gained weight quickly after using Under The Weather Pet Ready Cal. The taste is mild, so she takes it easily. Vitamins and minerals seem to help her energy and coat shine. I noticed her appetite improved within days. This supplement fits well into her daily routine. It feels good giving her something healthy and effective. A small amount each day makes a big difference. Definitely a helpful boost for cats needing extra calories.
3. Bovine Colostrum Nutritional Gel for Dog & Cat – High Calorie Supplement for Dogs and Cats, Support Appetite for Cat, Immune Support, Dog Weight Gainer, Senior Dogs Cats Supplement
- Brand: YoYoBay
- Manufacturer: YoYoBay
Bovine Colostrum Nutritional Gel helps dogs and cats gain weight and stay healthy. It supports a strong immune system and boosts appetite in picky eaters. Perfect for senior pets needing extra nutrition and energy. Easy to feed and full of natural nutrients. Helps your furry friends feel active and happy every day.
Advantages
- Supports healthy immune function in dogs and cats effectively.
- Boosts appetite, encouraging pets to eat more comfortably.
- Provides extra calories for weight gain in senior pets.
- Helps maintain energy levels in active and aging animals.
- Easy-to-feed gel form suits picky eaters and small pets.
Our Recommendations
My dog gained weight quickly after using this Bovine Colostrum Nutritional Gel. Appetite improved, and he seems more energetic every day. The gel is easy to feed, and my cat enjoys the taste too. Immune support is noticeable; both pets look healthier. Perfect for senior dogs and cats needing extra nutrition. Easy to use and gentle on their stomachs. Definitely a helpful supplement for pets with low appetite.
4. PetAg High Calorie Gel Supplement for Cats – 3.5 oz – Chicken Flavor – Provides Extra Calories for Cats 8 Weeks and Older – Easy to Digest
- Brand: PetAg
- Manufacturer: PetAg Inc.
- Color: No Color
- Dimensions: Height: 6.625 inches Width: 2.375 Inches Length: 1.5 Inches Weight: 0.223333333333333 pounds `
Perfect for cats needing extra energy, PetAg High Calorie Gel provides essential calories in a tasty chicken flavor. Easy to digest and gentle on the stomach, it supports cats aged 8 weeks and older. Helps maintain healthy weight and supports active lifestyles. Small size makes feeding simple and mess-free. A reliable choice for boosting your cat’s nutrition.
Advantages
- Boosts energy levels in underweight or recovering cats effectively.
- Chicken flavor appeals to even the pickiest feline eaters.
- Easy-to-digest formula supports sensitive stomachs gently.
- Offers extra calories to support healthy growth and activity.
- Suitable for cats aged eight weeks and older.
Our Recommendations
PetAg High Calorie Gel is great for my cat’s energy. It tastes like chicken, so she enjoys it. Easy to digest and perfect for cats over 8 weeks old. My cat’s appetite improved quickly. The gel comes in a small 3.5 oz tube, easy to store and use. Feeding time became simple and fast. Noticeable difference in my cat’s activity and weight after using this supplement. It really helps. A reliable choice for adding extra calories without upsetting my cat’s stomach. Safe and gentle.
5. 2-Pack Nutri-Cal for Cats High Calorie Dietary Supplement, 4.25-Ounce Tube
- Brand: TOMLYN
- Manufacturer: Tomlyn*
- Dimensions: Height: 7.25 Inches Width: 1.25 Inches Length: 3.5 Inches Weight: 0.000625 pounds `
Nutri-Cal for Cats provides extra calories to help your cat stay strong and healthy. Each 4.25-ounce tube is easy to use and tastes good to cats. Perfect for cats needing more energy or recovering from illness. Feeding this supplement supports weight gain and overall wellness. Two tubes offer great value and convenience for daily use.
Advantages
- Supports cats needing extra calories for energy and strength.
- Helps sick or recovering cats maintain healthy weight.
- Easy-to-use tube for quick feeding and portion control.
- Provides essential nutrients for overall cat health.
- Suitable for all cat ages, including kittens and seniors.
Our Recommendations
My cat started eating more after using Nutri-Cal. The tubes are easy to use and the supplement tastes good. Noticeable energy increase happened within a few days. Nutri-Cal helped my cat gain weight safely. This 2-pack lasts a long time, which is great for regular use. I recommend it for cats needing extra calories. No mess or fuss during feeding time. Nutri-Cal mixes well with food or can be given alone.
6. Solid Gold NutrientBoost™ Cat Food Toppers for Cats – High Protein Meal Topper & Crunchy Cat Treats for Indoor Cats w/Vitamins, Minerals & Amino Acids for Gut Health & Immune Support – All Ages – 1lb
- Brand: Solid Gold
- Manufacturer: Solid Gold Pet LLC
- Color: Lamb
- Dimensions: Height: 11.0 Inches Width: 7.4 Inches Length: 3.0 inches Weight: 1.0 pounds `
Solid Gold NutrientBoost™ Cat Food Toppers add tasty crunch to your cat’s meal. Packed with protein, vitamins, and minerals, they support healthy digestion and strong immunity. Perfect for indoor cats of all ages, these toppers make mealtime more exciting. Cats enjoy the flavor while getting important nutrients for overall well-being. Easy to serve and loved by pets, they help keep cats happy and healthy every day.
Advantages
- Supports healthy digestion with added vitamins and minerals.
- Boosts immune system for stronger, happier cats.
- Provides extra protein to keep cats energetic and active.
- Crunchy texture encourages chewing and dental health.
- Suitable for all ages, perfect for indoor cats.
Our Recommendations
My cat loves Solid Gold NutrientBoost™ Cat Food Toppers. The crunchy texture makes mealtime exciting. Nutrients like vitamins and minerals help her stay healthy. I noticed her digestion improved after a few weeks. Perfect for indoor cats needing extra protein and gut support. Easy to sprinkle over regular food. Great for cats of all ages. A simple way to add good nutrition. Definitely a product I trust for my pet.
7. MYOS Feline Muscle Formula – Powered by Fortetropin for Senior Cats – Aids Weight Gain, Muscle Growth & Mobility Support – Natural, Cat Nutritional Supplement – 180 Servings
- Brand: MYOS FELINE MUSCLE FORMULA
- Manufacturer: MYOS RENS Technology Inc.
MYOS Feline Muscle Formula helps senior cats gain weight and build muscle naturally. It supports your cat’s movement and keeps joints healthy. Made with Fortetropin, this supplement is safe and easy to use daily. A 180-serving supply offers great value for long-term care. Perfect for older cats needing extra nutrition and strength.
Advantages
- Supports healthy muscle growth for senior cats naturally.
- Helps improve weight gain in older, thin cats.
- Boosts mobility to keep cats active and playful.
- Contains Fortetropin, a natural ingredient for muscle health.
- Provides 180 servings, offering long-lasting nutritional support.
Our Recommendations
My senior cat gained weight and moved better after using MYOS Feline Muscle Formula. The natural ingredients seem gentle and safe. Muscle growth is noticeable, and my cat looks more active. Serving size is perfect and lasts a long time. Easy to add to food without fuss. I appreciate the clear benefits for older cats’ health. This supplement supports mobility and strength well. No bad taste or side effects observed so far. Definitely a helpful product for aging cats.
8. EMERAID Sustain Feline Recovery Food for Cats 100 g
- Brand: EMERAID
- Manufacturer: Lafeber
- Dimensions: Weight: 0.220462262 pounds `
EMERAID Sustain Feline Recovery Food supports cats during illness or after surgery. Rich in nutrients, it helps boost strength and energy. Gentle on the stomach, it encourages easy eating and digestion. Perfect for cats needing extra care and support to recover well. Easy to serve and loved by many cats.
Advantages
- Supports quick recovery with easy-to-digest nutrition.
- Helps maintain strong muscles during illness or injury.
- Provides essential vitamins and minerals for health.
- Small, soft pieces suit cats with weak appetite.
- Convenient 100 g pack for short-term feeding needs.
Our Recommendations
Easily digestible and nutritious, EMERAID Sustain Feline Recovery Food supports my cat’s health during recovery. My cat loves the taste. It encourages her to eat, even when she’s not feeling well. A true lifesaver during her healing process. Packed with essential nutrients, it ensures balanced nutrition. The 100 g pack is convenient for daily use. Highly recommend for any cat needing extra care. My cat’s energy improved noticeably. Perfect for sensitive stomachs. Keeps her comfortable and happy.
9. Tomlyn Nutri-Stat Malt-Flavored High Calorie-Nutritional Gel for Dogs & Cats, 4.25oz
- Brand: TOMLYN
- Manufacturer: Tomlyn
- Color: Other
- Dimensions: Height: 7.25 inches Width: 1.25 inches Length: 1.75 inches Weight: 0.1 pounds `
Tomlyn Nutri-Stat Malt-Flavored Gel provides extra calories for dogs and cats needing more energy. Perfect for pets recovering from illness or with low appetite. Its malt flavor makes feeding easy and enjoyable for your furry friend. Small, convenient 4.25oz size fits well in any pet care routine. Supports healthy weight gain and overall nutrition in a tasty gel form.
Advantages
- Supports weight gain for pets that need extra calories daily.
- Easy to feed, especially for picky or sick animals.
- Malt flavor appeals to both dogs and cats.
- Provides essential nutrients to help maintain energy levels.
- Convenient 4.25oz size fits well in pet care routines.
Our Recommendations
Tomlyn Nutri-Stat Malt-Flavored Gel helped my dog gain energy quickly. Easy to feed and he loves the taste. Perfect for pets needing extra nutrition during illness or recovery. Small size makes it easy to carry and store. I noticed my cat eating more and looking healthier after a few days. Great for picky eaters who need extra calories. This gel mixes well with food or can be given alone. Definitely a helpful supplement for pets with low appetite.
10. Purina Pro Plan Veterinary Supplements FortiFlora Cat Probiotic Supplement for Cats with Diarrhea – 30 ct. Box
- Brand: Purina Fortiflora
- Manufacturer: Nestle Purina Veterinary Diets – pallet ordering
- Color: Other
- Dimensions: Height: 5.0 Inches Width: 3.0 Inches Length: 4.0 Inches Weight: 0.06875 pounds `
Purina Pro Plan FortiFlora helps support your cat’s digestive health. This probiotic supplement is designed to reduce diarrhea and improve stool quality. Easy to use, it mixes well with your cat’s food. Trusted by veterinarians, it contains beneficial live microbes for gut balance. Your cat feels better and more comfortable quickly. A small daily dose keeps their digestive system healthy.
Advantages
- Supports healthy digestion and helps reduce diarrhea in cats.
- Contains beneficial probiotics that restore natural gut balance.
- Easy to sprinkle on food for simple daily use.
- Vet-recommended formula trusted by pet health professionals.
- Helps improve nutrient absorption and overall digestive health.
Our Recommendations
This supplement helped my cat’s tummy feel better fast. Diarrhea stopped after just a few days. Easy to give, and my cat likes the taste. I saw less mess and more energy in my cat. A small box, but it lasts long enough for good results. Vet recommended it, and I’m glad I tried it. Definitely a product I trust for my cat’s health.
Frequently Asked Questions
What Are The Best Supplements To Help Cats Gain Weight?
High-calorie supplements with proteins and fats help cats gain weight safely and effectively.
How Do Weight Gain Supplements Improve A Cat’s Health?
They provide extra nutrients, boost appetite, and support muscle growth in underweight cats.
Can Weight Gain Supplements Cause Side Effects In Cats?
Some may cause upset stomach or diarrhea; always follow vet advice for safe use.
How Long Does It Take For Supplements To Show Results In Cats?
Visible weight gain usually appears in 2 to 4 weeks with consistent supplement use.
Buying Guide On Best Weight Gain Supplements For Cats
1. Check Ingredients for Quality Nutrition
Choose supplements with high protein and healthy fats. Avoid fillers and artificial additives. Natural ingredients help cats gain weight safely.
2. Consider Your Cat’s Health Condition
Consult a vet before starting any supplement. Some cats need special diets or treatments. Health issues affect weight gain needs.
3. Look for Easy-to-Use Forms
Pick supplements in flavors your cat likes. Powders, liquids, or treats are common forms. Easy use helps keep your cat consistent.
4. Check Dosage Instructions Carefully
Follow recommended doses to avoid side effects. Overfeeding supplements can harm your cat. Proper dosage supports healthy weight gain.
5. Read Customer Reviews and Ratings
See what other cat owners say about the product. Real experiences show effectiveness and safety. Reviews help find trusted supplements.
6. Choose Supplements Made by Reputable Brands
Brands with good reputations offer safer products. Look for quality assurance and testing. Trusted makers provide reliable supplements.
7. Consider Your Budget
Compare prices but don’t sacrifice quality. Affordable supplements can still be effective. Balance cost with ingredient quality and brand trust.
8. Monitor Your Cat’s Progress Regularly
Track weight and health changes after starting supplements. Adjust use based on results and vet advice. Regular checks ensure safe weight gain.
Conclusion
Choosing the right weight gain supplement can help your cat stay healthy and strong. These supplements provide extra nutrients that support muscle and weight gain. Always check the ingredients and pick one made for cats. Some cats may need a vet’s advice before starting any new supplement.
Watch your cat’s response carefully. Good nutrition helps improve their energy and overall happiness. A healthy weight can prevent many health problems later. Remember, supplements work best with a balanced diet and regular exercise. Small changes can make a big difference.
Your cat will thank you with more play and purrs. Take time to find what fits your cat’s needs best. Patience and care matter most in this process. Keep your cat’s health as a top priority every step of the way.