So your dog seems too skinny for his breed.
Now you’re diving in the web in hopes of learning how to get a dog to gain weight. Fortunately, you have stumbled upon the right page. In this article, we will tackle how to help an underweight dog in various ways.
Size really does matter from a health point of view. Whether your current dog is too slim or you had the kind heart to rescue a vulnerable, starving dog, the info below will guide you.
How to know if my dog is underweight?
Now that’s a good question. For all you know, your dog is not actually underweight and you’re just too concerned. But to settle things and for your peace of mind, the best way to determine the health status of your dog and whether he has the right weight is to consult your vet. No online advice can practically beat a professional’s statement. Moreover, your vet can also evaluate the right weight goals since some breeds have a naturally stockier or slimmer look.
There is no universal “normal” look among all dogs as breeds basically differ from each other. For instance, a greyhound can look boney with all the hip bones and several ribs – but can still be considered healthy. However, the same “boneyness” level in other breeds might infer malnourishment.
This reminder can also be applied on the flipside. A stuffy Chihuahua or Labrador doesn’t mean the pet is healthy. While this might sound a bit confusing for you, this visual graphic from Purina can greatly help in knowing whether your dog is under- or overweight.
Feeding the right food
The quality of the food your dog eats is far more vital than its quantity. Most pet parents settle with giving their dog as much food as they can without knowing it’s entirely wrong. The best way to get a dog to gain weight is to feed him the right kind of food and NOT feeding with a lot.
1. Moderately underweight
PetMD suggests a dry dog food that contains 28-30% protein and 18% fat content.
Try to see the best dry dog feed here.
Your dog’s diet must not be predominantly carbohydrate but just have enough levels of it. Simply put, a moderately underweight dog needs a moderately high in fat and protein diet.
2. Truly underweight
For a dog that really looks starved and markedly underweight, he needs an even higher fat content in his diet. The trick here is NOT to overfeed your dog in a single meal. Remember to start out slowly and work your way into feeding him more in his recovery process (more on that later).

Feeding a proper amount of food
When food-deprived, know that your dog’s stomach doesn’t shrink. However, minimal-to-zero food intake has a negative impact on the stretch receptor nerve impulses. What does it mean? Your dog will tend to feel full sooner than he would on a normal stomach. This is the reason why you should not overfeed him at a single blow.
As a human, you probably have experienced it yourself the feeling of extreme discomfort due to continued eating after you ignore your stomach’s signals of being full.
That said, overfeeding an emancipated dog can lead to serious problems since they are physically unable to consume large amounts of food. The golden rule: do not feed too much and too quickly. It’s not how to get a dog to gain weight fast.
1. Resting energy requirement
According to Wisconsin Federated Humane Societies, you should feed a starving animal by starting at 25 percent of their RER (resting energy requirement) for the first day.
2. How to calculate RER
It’s easy. Just take your dog’s weight in kilograms, multiply by 30 and add 70. If you have a calculator, simply follow the formula:
(Dog’s weight kilogram x 30) + 70 = RER
You can also refer to this comprehensive table prepared by Pet Obesity Prevention to guide you in determining your dog’s RER.
3. After the first day
So you’ve successfully fed your dog the first day with the 25 percent RER rule. Now the amount must be gradually increased by another 25 percent on a daily basis until such day the full amount is reached. That way, you can effectively dodge the risk of refeeding syndrome.
Note: Refeeding syndrome is a condition where a dog (or any animal for that matter) suffers from seizures, cardiac abnormalities, muscle weakness, diarrhea, and nausea – all because someone feeds them too much and too quickly. This is fatal especially for rescued, starving dogs.
4. After the RER requirement stage
If you have successfully surpassed the RER requirement stage where you no longer have to worry about refeeding syndrome, it’s time to feed the dog in normal amounts.
Now that your dog’s stomach can finally accommodate a full meal, what’s left for you is to determine the recommended serving size for his particular breed. The best dog food brands should have a serving size suggestion printed at the back of each box. You simply have to take time reading some stuff and feed your dog with the right amount.
Feeding at the right time
As equally important as feeding the right food and quantity, feeding at the right time is also a must. You can’t just give your dog a meal whenever you want to.
- A normal healthy dog is fed up to twice large meals every 24 hours. If you have a skinny canine, you will have to divide these two (2) large meals into smaller portions.
- Split the food into four (4) meals and feed your dog in four (4) evenly spaced time intervals throughout the day.
Consult the vet
While you can browse for endless info across the web – including this page which, in itself, is already a form of help – nothing still beats what the professionals have to say. It’s always a rule that the vet knows best.
If you’re bringing a rescue dog home (regardless if your new canine friend is underweight or not), the first thing to do is to let a vet check him. The vet can properly assess the needs of your dog and can guide you on your way to improving his overall wellbeing. You should also take note of their recommended supplements and particular brands.
Make a food log
Part of the steps of how to get an underweight dog to gain weight is to simply keep track of his progress. And you can do it by making a food log. There’s no better way of knowing whether your efforts are working or not.
- What you have to track is the quantity of food you give them and how much of that food is eaten.
- Keep your food log next to where you store your dog’s food. That way, it’d be virtually impossible to forget using it.
- You can also use the same food log to track of your dog’s weight in the process so you’ll see the results over time.
- If you have a picky canine pet, take this opportunity to evaluate what type of ingredient or food product they don’t like to eat.
- Ultimately, your food log serves as your report that tells you whether it’s time for another vet visit or is it time to try something different.
Try using supplements
It’s also advisable to fill in dietary gaps. During their time without food, your dog loses a lot of essential vitamins and minerals. You can help them rebuild what they have lost by letting them take supplements. For your specific breed, it’s best to talk with your vet first. Just make sure that your dog gets to have omega-3 and omega-6 fatty acids.
Summary
The ideal body condition can only be achieved by a healthy dog weight. While you obviously love your dog the way he is, it won’t hurt if you try to promote gaining a few pounds especially if you have confirmed that he’s indeed underweight.
For your underweight dog needs, you can always refer to the above info and relearn how to get a dog to gain weight.