Skip to Content

How to Fatten Up a Dog – 11 Top Tips

Do you have an underweight dog?

Worried pet owners sometimes think the worst. It’s true that there are serious conditions like cancer that can cause weight loss. Most of the time, however, reasons why a dog isn’t gaining weight is a simple fix.

If you’re worried because your new puppy (or older dog) is losing weight, this post is for you. By the end of this post, you will understand:

  • Common reasons why some dogs have trouble putting on enough weight.
  • Identify signs of underlying health conditions.
  • Get useful tips on how to help fatten up your dog the healthy way.

The first thing you need to do is have your dog checked by a veterinarian. It’s important to know whether your dog has any underlying health conditions. Sometimes just treating these conditions will set your dog on the road to healthy weight maintenance

Why Is My Dog so Skinny?

A dog’s weight can fluctuate from time to time. A few pounds up or down is normal. Puppies normally have a little extra fat on their bones.

Older dogs may lose weight over time due to loss of appetite, changing activity levels, or illness.

The most important thing to do is eliminate the possibility of illness.

Have your dog seen by a licensed veterinarian as soon as possible. In some cases, identifying and treating underlying conditions may be the trick to helping your dog gain weight.

Common reasons why your dog may be having trouble maintaining or gaining weight include:


Dogs are very good at hiding pain. Unfortunately, the pain they’re feeling may have a negative impact on their appetite

Stress or Anxiety

Just like humans, dogs are affected by stress and anxiety in a number of ways. If dogs are experiencing any kind of fear, they’re not likely to be hungry. Unfortunately, if this fear or distress is ongoing, it can cause serious health problems for your dog.

Picky Eater

A dog’s appetite will naturally increase when he/she is motivated by the type of food offered.

Some people “cure” a picky eater by applying food toppers to their dog’s food. This gives the dog a sense of eating different food and can excite the appetite.

Medical Conditions

As dogs mature and reach old age, the risk of medical conditions begins to rise.

If you have a senior dog who suddenly stops eating, it’s time to visit a veterinarian. Keep in mind that it doesn’t always mean your dog has a serious disease.

Some dogs may be having dental problems that warrant a change in diet. Their taste buds may have changed with age or they simply don’t need the same amount of calories that they once did.

Adding food toppers can stimulate a dog's appetite

Intestinal Parasites

Sometimes a rescue dog may come to you full of parasites.

Most non-profit organizations will screen and treat parasites, but not always. Parasites can cause a number of problems for dogs including anemia (which causes fatigue and loss of appetite).

In this case, the easiest way to get your dog back to a normal weight is by treating the parasites.

This is best done by a licensed veterinarian. He/she may want to test for heartworms, tapeworms, ringworm, roundworm, and other parasites.

The veterinarian will likely recommend a topical or oral anti-parasitic treatment.

Very High Metabolism

Some dogs, like the greyhound, naturally have high metabolism.

If your dog is not gaining or maintaining a healthy weight, it could be he/she has a high metabolism. In this case, you may want to offer higher protein foods that are especially made for your breed.

Recent Illness

If your dog is recovering from surgery or has recently been sick, it might take some time for his/her appetite to return to normal. It’s important to make sure your dog gets adequate water intake to avoid dehydration.

If your dog still has a reduced food intake after a couple of days, be sure to mention it to your veterinarian. That said, if your dog is refusing to drink water, he/she needs a veterinarian right away.


In some cases, dogs just aren’t getting enough calorie intake. The number of calories a dog needs a day can vary depending on his/her activity level.


As dogs age, their activity levels tend to lessen. This could be because of joint problems or other mobility issues. If you have a senior dog, it might be time to change the kind of food he/she eats.

Switch to food specifically made for senior dogs and encourage your dog to eat by using nutritious food toppers.

Sudden Weight Loss in Dogs – When to Worry

Severely underweight dogs often have difficulty eating because they are often suffering from underlying medical problems. Weight loss can be a symptom of illnesses like:

  • cancer
  • diabetes mellitus
  • liver disease
  • kidney disease, etc.
  • food allergies

If your dog is experiencing unusual signs and symptoms in conjunction with weight loss, contact a veterinarian for an appointment.

If your dog has any kind of secondary illness, it might not be possible to help him/her gain weight until the condition is treated.

Serious conditions warrant medical attention. A few signs your dog may be sick include:

  • depression
  • low energy
  • dull or unusually shedding coat
  • low appetite
  • increased thirst
  • increased or frequent urination

How Much Should My Dog Weigh?

The appropriate weight of your dog depends on whether they are male or female. Breed type also plays a big role in how much your dog should weigh.

To determine whether your dog is at a healthy weight, The described technique applies to all breeds. All you have to do is:

  1. Look at your dog’s body from a variety of angles.
  2. Do a rib check.
  3. Look at your dog’s profile
  4. Do an overhead check.

Have a look at the infographic at the bottom of this post for more details.

too much fat can cause digestion problems in dogs

Examples of a Dog’s Ideal Weight by Breed

The American Kennel Club offers a complete list of breeds and what they should weigh. The following is a partial list for your comparison:


Chihuahua – no more than 6 pounds.

Papillons – 5 – 10 pounds male or female

Yorkshire Terriers – 7 pounds male or female

Shih Tzu 9 – 16 pounds male or female


Welsh Terriers 20 pounds male – females are proportionally smalle

Whippets 25 – 40 pounds male or female

Staffordshire Bull Terriers 28 – 38 pounds male and 24 to 34 pounds female


Coonhounds – 50 – 70 pounds male or female

Spaniels (Irish Water) 55 – 68 pounds male and 45 – 58 female

Standard Schnauzers 35 – 50 pounds male and 30 to 45 pounds female


Tibetan Mastiffs 90 to 150 pounds male and 70 – 120 pounds female

Mastiffs 160 – 230 pounds male and 120 – 170 pounds female

Newfoundland Dogs 130 – 150 pounds male and 100 – 120 pounds female

Visit for a full list.

Safe Ways To Fatten Up Your dog

In order to get to your dog’s ideal weight, you’ll want to set up a feeding schedule to get him/her used to the diet changes. It’s always good to consult a veterinary nutritionist for the most up-to-date recommendations. However, the following suggestions are a good place to start.

#1. High Quality Meats

Though they’ve adapted closer to a human lifestyle, dogs are still mostly carnivorous animals. More of the essential amino acids a dog’s body needs will be found in animal protein, while these are much harder to find in plant proteins.

These also taste great. Add some cooked or raw meat to your dog’s meals if you’re having trouble encouraging him/her to eat.

#2. Higher Calorie Food

Look for dog food that is specially formulated to add extra calories to your dog’s diet.

#3. Add Dog-Safe Human Food To Your Dog’s Diet

Not all human-grade food is safe or appropriate for your dog. However, there are a few things you can safely add to your dog’s diet including:

  • Add Eggs
  • Full fat cottage cheese
  • Lean raw meat
  • Lean cooked meat
  • Quinoa – contains the amino acids needed for muscle mass
  • Peanut butter – moderation
  • Sweet potatoes

Be careful about the types of food you feed your dog. Some pet owners resort to empty calories to help fatten up their dogs. This, unfortunately, can backfire. You want your dog to reach a healthy weight – not become overweight.

Read this hand-picked posts for a better understanding of what not to feed your dog (or how to feed in moderation):

Can My Dog Eat Cheerios? 9 Nutrition-Savvy Tips for Dog Owners

Is Blackstrap Molasses Safe For My Dog to Eat?

Can My Dog Eat Tortillas? 9 Potential Health Risks in Dogs

Should My Dog Eat Beef Jerky? 11 Surprising Pros & Cons

Can Dogs Eat Ginger Snaps? 5 Important Things to Consider

#4. Don’t Skip Grains, Vegetables & Fruits

Most dog owners have heard of the ‘grain-free’ craze, and many swear by it! Far fewer know exactly why they are avoiding grains, however.

Many cheaply made dog food brands will pack their products full of starchy, carb-rich vegetables.

Plant products are far cheaper to grow and harvest than animals are to raise and slaughter. This often leads to weight gain and obesity.

Too much can be harmful, but you never want to eliminate it altogether. A great dog food diet will offer a little bit of everything.

Even some of the most expensive, highest quality brands on the market will offer these things (after prioritizing animal products).

Note: Though you want your dog to gain weight, too many sugars can cause health problems like diabetes. Fattening up your dog with carb-rich foods may not be the best alternative.

You also generally want to avoid feeding too much human food. Human foods are often high in either sodium or carbohydrates.

Always research any human foods before they are offered because some can harm out pets.

Even if they are ok for a dog to eat, most human foods should only be given as an occasional treat.

#5. Feed Multiple Daily Meals

If your dog is underweight, we suggest you divide your dog’s daily recommended caloric intake/feeding amount into 4 smaller portions instead of the single or twice daily meals most adult dogs eat.

Large meals, especially offered all at once, can cause digestive issues.

Monitor how much your dog eats closely at each meal!

You might begin a chart to list your daily recordings. You’re able to compare how much is eaten, and in turn, calories consumed each day. Then you can easily mark improvements.

#6. Gradually Change Meals if Needed

You might want to switch to a different meal or dog food brand. Maybe your veterinarian has suggested you switch to a more nutritious food.

You never want to simply switch to feeding something completely different right away. Rapidly changing a dog’s diet can lead to GI upset, cause vomiting/diarrhea, and make matters worse.

Instead, start by mixing a little bit of the new food in with the old at each meal. Gradually increase the amount of the new food over the following days, a small portion at a time!

#7. Increase Caloric Intake With High Quality Food

If a healthy animal burns more calories than he consumes, he’ll usually lose weight. This may seem like a very general principle, but it is universal. There are several factors that stem from this, but the principle is basic.

An animal will gain weight if he consumes more calories than he burns.

Begin slowly increasing the meal size of your dog’s four daily meals, assuming he eats 100% of all of them.

#8. Add Water to Your Dog’s Food

Some dogs, especially those with dental issues,may have trouble chewing solid kibble.

Not only will adding water help soften that food, but it will also help rehydrate a dog in need of more fluids.

In the case of something like Parvo or Distemper, your dog will absolutely need medical attention and likely need intravenous fluid therapy. Your dog may stop eating altogether. Seek veterinary care immediately and don’t try to treat these on your own.

#9. Add a Nutritional Supplement to Meals

It’s possible an underweight dog is nutrient deficient. Your macro-nutrients include protein, fats, and carbs, but micro-nutrients also include vitamins and minerals.

Broad-spectrum vitamins support a wealth of areas, while Omega fatty acids are also important.

#10. Raw Diet

Dogs switched too quickly to a raw diet could lose weight. To help your dog gain back a healthy weight, switch him to more muscle meat. Muscle meat includes tripe, lungs, heart, animal tongue and raw animal fat.

#11. Free Feeding

 Try leaving your dog’s daily serving of food out all day. This allows your dog the opportunity to eat when hungry.

You also might want to ask your veterinarian to help you develop a feeding plan for your little one.

Is your dog a healthy weight infographic

At The End of the Day

There are many ways you can fatten up your dog if he is underweight or not eating well, several of them are listed above.

The most important thing you can do is first understand why he’s underweight and what is causing those poor eating habits!

For example, your pet might be underweight or refuse to eat due to a medical issue. Simply feeding more may not help. You’ll want to treat the medical issue first, which will probably require the assistance of a veterinarian.

It’s usually recommended an underweight dog be placed on a high fat, high protein diet.

You’ll want to increase feeding times to 4 smaller meals a day, and make sure these meals are easily eaten. Water them down if necessary.

Don’t forget to chart and track your pup’s progress! Be sure to eliminate any medical causes that may be discouraging your pooch from eating.

I want to thank you for taking the time to read this post. Please take a second to share with your social followers. It means a lot and actually helps to keep this blog up and running.

Frequently Asked Questions About How to Fatten Up a Dog

Will eggs help my dog gain weight?

In some dogs, plain cooked eggs are a good option to add calories to their regular meal. Dogs should only eat one egg a day. Make sure the egg doesn’t have added salt or seasonings and isn’t fried.

Check with a veterinarian before changing your dog’s diet in any way. This includes adding eggs to your dog’s diet on a regular basis.

Why Won’t My Dog Eat Even Though They Seem Hungry?

There are different reasons why a dog won’t eat. It could be that he just doesn’t like the food. Other reasons why your dog won’t eat could be related to dental issues.

Thank you for reading this post!

I want to take a moment to thank you for reading this post. I hope you found it useful and informative. If so, could you take a second to spread doggy love through social media?

You'll find the buttons at the top of this post and at the bottom of the post. might have noticed a little heart at the bottom left of your screen? Give it a click if you want to bookmark this page for future reference.