8 Best Weight Gain Supplements For Dogs

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If your dog is on the skinny side, they might benefit from the best weight gain supplement for dogs. Most dogs maintain a healthy weight by eating their food consistently, but there are plenty of dogs that have trouble gaining weight. Senior dogs and rescue dogs from neglectful pasts often need weight gain supplements the most.

Changing your dog to high-calorie food might not make sense. If dogs are picky or sensitive, switching them to a new diet may cause problems. So, many pet parents turn to weight gain supplements to help their dogs bulk up without drastically changing their routine.

Does your dog need to lose weight instead? Check out the  Best Dog Weight Loss Supplements.

Should You Consider the Best Weight Gain Supplements for Dogs?

With so many overweight dogs in the world, most dog parents don’t need to think about weight gain supplements. Yet, there are plenty of instances where a little weight gain could go a long way for a dog’s health. If your vet informs you that your dog is underweight, you should take action.

Weight loss happens gradually over time, but an easy way to spot an underweight dog is to look at their body shape. If their bones are easily visible, such as their hip bones and rib bones, they need to gain some weight. If they have an hourglass figure instead of a small indent at the waist, that’s another sign that they’re underweight.

Weight Gain for Senior Dogs

Many older dogs naturally lose weight as they age because they may lose muscle mass, have worse digestion, and have less appetite. Building up their muscles or switching their food isn’t as easy as it was when they were younger, so weight-gaining supplements are the easier choice for many families with senior dogs.

Weight Gain for Rescue Dogs

When you adopt a dog, there’s a chance they’ll be underweight. Many rescue dogs were abused, neglected, or strays before someone saved them, so they may still be malnourished. Using a weight gain supplement is an easy way to help a rescue dog gain healthy weight so they can thrive in their new life.

Best Weight Gain Supplement for Dogs

If you have an underweight canine, one of the following weight gain supplements could help improve their health.

1. MVP K9 Formula Mass Weight Gainer for Dogs

This powder supplement is designed for dogs who are underweight and need to gain weight quickly. It can also improve your dog’s muscle growth and energy levels. To serve, you can pour some of the powder on your dog’s meals. Many dogs enjoy the flavor, so it may entice them to eat their food more often too. This product has a short ingredient list that avoids fillers, salts, and sugars, so it can even help sensitive dogs gain weight. It’s designed to help every dog breed, from tiny French Bulldogs to massive Rottweilers.

Features:

• Flavorful powder supplement
• Helps dogs gain weight quickly
• Improves muscle growth and boosts energy
• Short ingredient list
• Works for all breeds

2. Dyne High Calorie Weight Gainer Liquid

Dyne’s High Calorie supplement comes in a liquid form. It’s high in calories and fats that can help a dog gain weight and recover from illnesses quickly. It also has added vitamins to ensure that there’s nutrition in those calories. This supplement even has proper nutrition for nursing mother dogs. You can feed it directly to dogs or pour it onto their food as a flavor enhancer. Many dogs enjoy the liquid’s vanilla flavor. A variety of dogs can benefit from it, but it’s especially beneficial for high-energy dogs that need additional calories to fit their active lifestyle.

Features:

• Vanilla-flavored liquid
• Can be fed directly or poured over food
• High in calories and fat
• Contains vitamins and other added nutrients
• Great for dogs with active lifestyles

3. Tomlyn Nutri-Cal High-Calorie Nutritional Gel for Dogs

This product is an oral gel that’s high in calories. Not only can it help dogs gain weight, but it also stimulates appetite and boosts energy levels. It’s packed with calories, nutrients, and omega fatty acids to give your dog a full health boost. It’s easy for dogs to digest, and the flavor is appealing to most canines. You can either serve it directly or put it on top of your dog’s food. It has formulas designed for adult dogs and puppies, so all dogs can benefit from this product. However, it’s most beneficial for aging, sick, or picky dogs.

Features:

• Easily-digestible gel
• High in calories, nutrients, and omega fatty acids
• Stimulates appetite and boosts energy levels
• Great for aging, ill, and finicky dogs
• Formulas for adults and puppies

Related: Best Dog Multivitamin Products

4. Miracle Vet High Calorie Weight Gainer

This high-calorie nutritional liquid is reviewed and recommended by veterinarians. The liquid is tasty and can be poured over your dog’s food or mixed with their water, so it’s great for stimulating an appetite. Always shake it before using it. It contains natural fish oil, which is packed with omegas 3 fatty acids to improve your dog’s skin, coat, heart, and joints. It also has many vitamins and minerals to keep your pup healthy overall. This product can boost the immune system, fight diseases, and improve energy levels. It’s made with natural ingredients that are safe for both dogs and cats.

Features:

• Liquid can be poured over food or mixed with water
• Stimulates appetite
• Contains natural fish oil
• Improves skin, coat, heart, joints, immune system, and energy levels
• Great for weight gain and recovery

Related: Best Eye Supplements for Dogs

5. Doc Roy’s Forti Cal High Calorie Nutritional Gel

This is another flavored gel that’s nutritional and high in calories. It tastes like beef and liver, so most dogs will happily gobble it up. You can serve it to your dog by giving it to them directly or using it as a food topper. It’s great for increasing weight, especially in dogs that are ill or have a lot of energy. As your dog eats it, you may also notice their appetite improve and their energy levels increase. All types of dogs can benefit from this gel, especially if they’re underweight.

Features:

• Nutritional, high-calorie gel
• Beef and liver flavored
• Great for helping sick dogs and hunting dogs gain weight
• Improves appetite and energy levels
• Works for all breeds

6. Buddy & Lola Dog Weight Gainer

Buddy & Lola’s supplement is a weight gainer that comes in powder form. It has a maple bacon flavor, so it’s a great choice for picky eaters. All breeds can benefit from this supplement, which can strengthen muscle mass, support underweight dogs, and improve skin and coat health. It’s especially beneficial for underweight rescue dogs. It’s safe for puppies and nursing dogs because it can promote growth and body tissue development. The easiest way to serve it is to pour the powder over your dog’s food, and the container includes a scoop to make serving easier.

Features:

• Maple bacon flavor
• The powder acts as a food topper
• Great for rescue dogs, puppies, and nursing moms
• Strengthens muscle mass and improves skin and coat health
• Beneficial for all breeds

7. Bully Max 3-in-1 Liquid Muscle Building Supplement 

Bully Max is a company that specializes in creating products that help dogs gain weight and build muscle mass. It’s especially effective for active, large-breed dogs, but it can be effective for all dogs as long as they’re 6 months or older. This liquid can be poured over your dog’s food, but picky eaters might not be interested in it. To make it more enticing to finicky pups, you can add plain yogurt or cottage cheese to the mixture. The formula contains astaxanthin, functional botanicals, and energy-dense oils to improve a dog’s weight, strength, and energy levels. It can also help dogs recover from illnesses faster.

Features:

• Helps dogs gain weight and build muscle mass
• Liquid food topper
• Ideal for large, active dogs, but works for all breeds
• Improves strength and energy levels
• Helps dogs recover faster

8. Vetoquinol Nutri-Cal Supplement for Dogs

This product is another flavored gel similar to the others mentioned on this list. It’s made for any pet who needs extra calories and vitamins, and it’s especially helpful for the growth of puppies and kittens. It can help boost energy levels, making it a good choice for high-energy dogs. This high-calorie supplement also contains omega-3 and omega-6 fatty acids to improve a dog’s skin and coat. It’s easily digestible, so it can stimulate an appetite. You can either serve this gel directly to your dog or put it on top of their food to enhance the meal.

Features:

• Flavorful gel supplement
• Packed with calories and nutrients
• Contains omega 3 and 6 fatty acids
• Stimulates appetite
• Boosts energy levels

Related: The Best Calming Supplements for Dogs

Buyer’s Guide for Weight Gain Supplements for Dogs

All the weight gain supplements on this list are effective, but not all dogs require the same supplements. So, here are some features to consider before making a purchase.

Calorie Content

A product needs to be high in calories to help your dog gain weight. Most people think of high-calorie products as unhealthy, but they’re a great way to help your pup gain weight fast. However, the best products will get those calories from ingredients that are beneficial for your dog’s health.

Ingredients

There are a lot of ways to add calories to a product, but not all of them will be healthy long-term for your dog. Before buying a supplement, look at the ingredient list to see if there are ingredients that can give your dog a health boost, such as items benefitting your dog’s skin, coat, heart, joints, digestion, and energy levels. If your dog has any allergies, make sure the product is free of those ingredients.

Supplement Form

The most common supplement form is gel or liquid. Some of those items have tasty flavors to appeal to dogs, while others are flavorless to blend in with your dog’s food. If you’re stuck between two products, consider what type of supplement your dog is most likely to eat.

Price

Finally, think about the price of the product. Is the amount of supplement and the quality of that product worth the cost? Sometimes, you’ll need to choose products that fit your budget, but other times, you might be willing to spend more to get a better-quality product.

Frequently Asked Questions

Here are some questions dog parents commonly ask when selecting an appropriate supplement.

1. Why is My Dog Losing Weight?

Sudden weight loss is often a sign of illness or stress in dogs. Cancer, hyperthyroidism, kidney disease, dental disease, and parasites can all reduce appetite and cause weight loss. If your dog is rapidly losing weight, visit your vet to rule out any life-threatening causes.

2. Why Won’t My Dog Eat Their Food?

If your dog normally eats but suddenly stops, pain or illness could be to blame. Talk to your vet, especially if other unusual symptoms are present. If you recently switched foods, your dog may dislike the flavor. Tasty food toppers can boost appetite without changing the main diet.

3. How Often Should I Feed My Dog?

Most adult dogs should eat about two meals per day—morning and evening. Puppies need smaller, more frequent meals. When in doubt, ask your vet for a schedule tailored to your dog.

4. Can Exercise Help a Dog Gain Weight?

Although exercise is often linked to weight loss, it can help underweight dogs build lean mass and feel better. Regular activity supports muscle gain and energy and should be paired with a calorie-appropriate diet or supplement.

5. Do Weight Gain Supplements for Dogs Have Any Side Effects?

Like any supplement, dog weight gain products may cause vomiting or diarrhea at first. If your dog is sensitive to new foods, start with a smaller dose and increase gradually per label directions or your vet’s advice.

6. How Long Until You’ll See Results with Dog Weight Gain Supplements?

Weight gain takes time. Expect roughly 4–6 weeks to notice visible changes, though timing varies by product and individual dog.

7. Can Stress Cause Weight Loss in Dogs?

Yes. Environmental changes, loss of a companion, or loud noises can trigger stress, reducing appetite or upsetting digestion. Identify and minimize stressors, consider calming strategies or supplements, and consult your vet if you suspect anxiety is affecting your dog’s weight.

8. Why Does My Dog Eat but Still Look Skinny?

Some dogs stay thin due to high metabolism, poor nutrient absorption, or underlying illness. Conditions like diabetes, parasites, or GI disorders can limit healthy weight gain. Active breeds may simply need more calories. If your dog remains thin despite eating, see your vet to check for medical causes and discuss nutrient-dense foods or supplements.

Safe and Effective Ways to Boost Your Dog’s Weight

The best dog weight gain supplements are essential if you have a skinny pup. Underweight dogs have weaker immune systems, less muscle strength, and weak joints. So, a supplement is an easy way to help your dog bulk up and get back to a healthy weight. Senior dogs, rescue dogs, and any other skinny dogs may spring back to life after taking one of these beneficial supplements.

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