How To Help Your Dog Lose Weight

Have you asked yourself, "Is my dog fat?" Being overweight will not only shorten your dog's life, it causes a serious decline in the quality of life he's got left. If you love him, help him slim down - starting now!


You would think by now I’d have learned my lesson and stopped telling people that their dogs are overweight. After all, I nearly lost one of my best friends over a spontaneous comment I made when I saw her dog for the first time in months – and the dog had positively ballooned in size since I had last seen her. (I blurted, “OMG! What happened to Carly? She got so fat!” And my friend didn’t talk to me for months after that.) But it seems like people just don’t recognize fat dogs when they have one! 

I usually manage to hold my tongue when it comes to strangers’ fat dogs. But not long ago I was attending a “puppy social” class with my new puppy Boone, and I saw a Labrador who probably weighed 50 pounds. Mind you, this was a class for puppies who were less than 20 weeks old. I felt that itch. “NO!” I told myself, “Don’t say anything!” But after the owner of the Lab asked how old Boone was, and I politely asked how old her pup was, it just burst out of me. “How much does your pup weigh?” I asked. And I added (tactfully, I thought), “She’s gigantic!”

“Oh, yes, she’s going to be a big dog,” the owner replied, laughing. “Both of her parents weigh more than 100 pounds. She’s just big!” But the puppy wasn’t just big, she was positively obese! 

 Anywhere there are dogs, whether at the pet supply store, dog park, or dog-training class, I find myself channeling the spirit of a combination Oprah Winfrey/canine diet proponent and pronouncing (but just inside my head): “Your dog is fat! And your dog is fat! And your dog is fat!” 

Look, I’m overweight, too. But this is a result of fully conscious choices I make for myself; I know what the result will be when I consume too many calories and don’t exercise enough. But our dogs don’t have any such understanding; their food intake and access to exercise – and thus, their body weight and condition – are completely up to us. When our dogs are overweight, it’s our fault. Period!

is my dog fat chart of dog weights
Get your dog to stand still and look at him from above. What’s the shape of his body from that view? It should have some indents at the shoulder and waist, not appear as a straight tube, nor bulge out like an overinflated balloon. ©Whole Dog Journal


Why do I care? How have I turned into the fat-dog sheriff? Why does it bother me so much when people allow their dogs to become so overweight? 

Here’s why: Dogs who are maintained at a healthy weight have a lower risk than fat dogs for many life-threatening health problems, including diabetes, kidney disease, metabolic and endocrine disorders, hypertension, and some forms of cancer. Older dogs with arthritis can remain ambulatory and active much longer if they are slender. Dogs with a lean body mass have fewer injuries to bones, muscles, and tendons than dogs who are carrying excess weight – and studies have shown that they live, on average, about two years longer than overweight dogs.

And it’s bad enough to see overweight older dogs. You are doing your dog a huge disservice if he’s under a year old and is already overweight. Make a growing puppy carry a lot of extra weight on his immature joints and you are practically signing him up for the development of painful arthritis at a prematurely young age.


So what how do you help your dog to lose weight? I thought you’d never ask.

1. Get an accurate, honest assessment of your dog’s condition. Make an appointment for your dog’s annual health examination. At that visit, let your veterinarian know that you are concerned about your dog’s weight and want her professional opinion: How much should your dog weigh, ideally? 

Every time I have offered my opinion to friends or family that I think their dogs are overweight – I’ve already admitted that this happens a lot – their first response is always the same: “Really? My vet has never mentioned that!” 

I suspect that many veterinarians are gun-shy when it comes to bringing up this topic with their clients; it probably makes most people defensive! But if you ask your vet for her opinion, and remain open and receptive to her answer, you just might learn that she’s been keeping her true opinion about your dog’s condition to herself. If she hesitates or waffles at all, ask a different question: “Do you think he should lose a little weight? Would he be healthier if he lost some weight?” 

2  Record a baseline and set a goal. Using the scales at your vet’s office, get an accurate weight for your dog. Write it down, along with the date. You could also use a cloth tape measure and record your dog’s girth just behind his front legs, at the widest place around his ribs, and where his “waist” is supposed to be (just behind his ribs).

Knowing your dog’s ideal waist measurement is probably impossible, but your vet should have been able to give you a number to strive for in terms of an ideal weight for your dog.

3. Aim for a weight loss of 3% to 5% of your dog’s body weight per month, or 1% per week. A 50-pound dog should lose about half a pound per week, or 2 pounds per month. 

4.  Feed your dog fewer calories. The number of calories your dog should be fed in order to maintain her ideal weight – not her current weight – is referred to as her “resting energy requirement (RER).” To determine your dog’s RER, convert her ideal weight in pounds to kilograms by dividing by 2.2. Then multiply that number by 30 and add 70.

Say I have a dog who weighs 100 pounds, but who should weigh about 90 pounds. Ninety pounds divided by 2.2 is 40.9 kg. Now I multiply by 30 and add 70:

40.9 x 30 = 1,227 + 70 = 1,297

1,297. That’s how many calories per day I should feed the 100-pound dog whose ideal weight is around 90 pounds. Now go check the number of calories in the food you give your dog. The food my dog is eating right now contains 380 calories per cup. So I’ll divide the number of calories my hypothetical fat dog should be getting by the number of calories in each cup of food:

1,297 ÷ 380 = 3.41 cups of food

“But wait!,” you say. “On the label of the food I feed my dog, it says I should be feeding a dog who weighs between 75 and 100 pounds between 4 3/4 and 5 1/2 cups of food per day!” What can I say? That’s probably how your dog ended up overweight! The sad fact is, most dog food labels overestimate dogs’ RER. They generally cover for this by adding the note, “Adjust feeding for optimal body weight.” 

 The moral of my example: Look at your dog’s food label to get the caloric content of the food, and calculate how much you should be feeding him based on his RER.

This amount may need to be adjusted in some cases. Dogs who are substantially overweight may do best with an interim target weight (rather than their ultimate ideal weight) to start with. Very active dogs may require up to 1.4 times their RER to keep their weight loss at a safe rate of no more than 5% per month. Puppies who are 4 months and older may need as much as 2 times their RER.

Of course, this addresses only the dog’s basic diet. If you feed a lot of treats, check the caloric content of the treats and reduce your dog’s food by about the amount of calories you are feeding him in treats. Because dog foods are complete and balanced and treats are not, however, you shouldn’t replace too many of his food calories with treats.

Most dogs care more about the number of treats they get than the size of each treat; it’s more rewarding for a dog to receive several small treats than one big one. Using tiny treats will help you reward your dog without adding too many extra calories. 

5. Weigh your dog frequently, especially when first starting a weight-loss program – at least once a week. If your dog is too heavy to pick up, you’ll need to go to your veterinarian’s office in order to get an accurate weight. 

Once your dog begins losing weight steadily, you can go longer between weigh-ins, but recheck at least twice a month to make sure you’re still on track. It’s easy to slip back into giving too much food and undo much of the good you’ve done if you rely solely on how your dog looks and feels. By the time you notice a difference, your dog could have gained a lot of weight back. 

6. Increase your dog’s exercise –but slowly. Regular exercise is also an essential component of a successful weight-loss program. Proper exercise not only burns calories, but also helps to burn fat and build muscle, improving body condition. As your dog loses weight and gains muscle, he will feel better and become more active, which will speed up the weight-loss process.

If your dog is not used to exercise, don’t try to do too much too soon. Start with very short sessions tailored to your dog’s capabilities, such as on-leash walks that gradually lengthen as your dog’s exercise tolerance increases. Don’t exercise your dog to the point where he is sore afterward. Non-weight-bearing exercise, such as swimming, is ideal for dogs with joint problems, and for other dogs as well. Again, start slowly, using a dog life jacket if that helps him to feel more comfortable in the water. 

If your dog is older or has health problems, consult with your veterinarian before beginning an exercise program. If your dog is really reluctant to exercise, it could be a sign that something’s wrong. A trial of pain medication can help you figure out whether your dog’s lack of activity is related to discomfort.

7. Keep your eyes on the prize: more time to enjoy with a healthier, happier dog. Your dog may not be happy about his new diet at first; he may start begging, counter-surfing, and even going through the kitchen trash, looking for a few extra calories. Give him a carrot to munch on – but don’t give in and give him fatty treats. Soon enough, as you begin to spend more time with him walking, and as his body begins to feel lighter and less burdened with all that extra weight, he’ll start to enjoy those walks more and worry less about how many kibbles are in his bowl. 


  1. Obviously over feeding is a major cause of weight problems in dogs but shouldn’t the article note (maybe it did and I missed it) that certain underlying conditions such as hypothyroidism can also contribute to excess body weight in dogs? This occurred with my GSD.

  2. I can identify with the author’s comment about people not liking you talking about the “elephant in the room! so to speak! I used to see a lady regularly with an obese chocolate Labrador. I managed not to make a comment until we were talking one day and she mentioned the dog was only 18 months old and had just had an operation for one if its elbow joints. I tried to be tactful and said “you’d be doing it a huge favour in getting rid of some of that excess weight then” but she glared at me and replied “My dog is not overweight he is stocky”. My reply was “Is that what your vet says?” and she answered “yes”. I found this hard to believe as dog resembled a Walrus more than a Labrador sadly. Other dog owners I met said her previous dog died too young due to obesity. Killing with kindness is still cruelty.

  3. To help clients and other dog owners with weight management for their dogs, I created a calorie estimator for both dogs and cats using all the vet formulas for RER and life stage calculations.
    It is a free download. It works with excel or google sheets.
    If your dog needs to lose weight, just enter the amount and it will calculate the number of calories to reduce each day and it will estimate the number of days to lose the weight based on the calorie reduction.
    I made a video on using the calorie estimator.

  4. Always have your dog’s blood work checked regularly. Our wonderful lab was getting bigger and bigger. We cut back food and exercised with little improvement. Vet did blood work and found he had cushings disease then told us to increase his food as we were actually starving this big boy who was probably not going to lose weight. He went back on his normal food and took natural meds and did exercise and lived another happy 6 years. He passed weighing 100 lbs. Always get a really good checkup before putting your pet on a diet.

  5. I once adopted an overweight dog and it took almost a year for her to lose the weight, keeping it at the recommended loss percentage you mentioned. I’m also currently fostering a dog who is very obese (though improving!). And who could forget Obese Beagle on Instagram! I’ve become much less judgy of the people I see with fat dogs, because they may not be the person who made the dog that way. Even though I’m not the one who made this dog fat, I am more likely to react negatively to someone who makes assumptions about me.

  6. Ack! Fat dogs (and actually any animal) are a pet peeve of mine. It is just not fair. They didn’t make the choice to have all the issues that obesity causes. Or to even get that way. I have a family member who has a two year old dog that is too heavy. I said something nicely and it fell on deaf ears. She honestly does not think he is fat. So I shut up. But it will be really hard to keep my mouth shut if he has issues later due to being too heavy. Both of our dogs had a few too many lbs when we adopted them. I worked hard to help them slowly lose weight and we are diligent about keeping it off. And they are well fed, get plenty of treats, healthy ones, and a good long walk, or swim daily. I try to explain to people that dogs can’t judge the size of a treat, so few tiny pieces of something are just as good as big chunks of something. And that a little bite of baked chicken breast is just as good to them as a hunk of cheese. But, ugh, waste of breath. So frustrating.
    I watch every morsel I put in my mouth to keep at a healthy weight. But my pets can’t. So I do it for them.

  7. Great article. Years ago we had a vet who told us “your dog weighs too much”. She advised us to use a measuring cup and how much to feed the dog at each meal and to cut down on the treats. Also raw crunchy veggies are healthier than dog biscuits and avoid feeding “people food” as treats.

  8. Thank you for the calculation. My vets were not helpful when discussing my overweight dog. One commented, “His head probably weighs at least 10 pounds” the other “we only get 1 semester in nutrition”. He was also on steroids for allergies and expected him to lose weight after stopping but he GAINED weight! We also give various vegetables to supplement to help him feel full and use a slow feeder. He runs in our woods, will walk 2 miles with me but doesn’t seem to lose.

  9. As a small animal vet, I would estimate that 2 out of 3 dogs I see are overweight or obese. The high-carb dry food that most people feed doesn’t help. Nor does using a “cup” that is a 42 oz. Big Gulp. (No lie, one of my clients ‘only’ fed his OBESE Lab 2 “cups” twice a day.) The client was horrified when I gave him a real actual 8 oz. cup. So sad.
    Thanks for a great article.

  10. We adopted a 9 year old English Lab/Mastiff mix who weighed 115 lbs. when we adopted him (down from 119 lbs. when he was surrounded). I immediately cut down on his food (he was getting 2 big horse scoops of food a day), and added green beans. We also started walking short distances, increasing as he was able to go further. At his best, we were walking an hour and 20 minutes a day (not all at once). He got down to 80 lbs. and looked magnificent.

    Sadly, the extra weight left its mark. He had hip dysplasia, arthritis, and his spine deteriorated to the point to where he could no longer stand, and we made the tough decision to euthanise him at 13.

    If his previous owner hadn’t over fed him, he would probably have lived a much longer life.

  11. What if you feed raw and bones as I do. I feed 6oz cube of raw ground meat (beef or tripe or offal) along with a frozen ducks neck or a piece of a Pork brisket bone. I sometimes include a spoonful of 3% fat greek yogurt and some leftover veg from our dinner. Is that too much? he doesn’t seem to be losing any weight. He is a 4 yr old Lab/Doberman mix who weighs 86 lbs. He weighed 87 lbs a couple of months ago so I guess I am making some progress but very slowly.

    • Is your dog eating anything aside from what you have listed? Vet opinion here—I would be concerned he is not getting the proper nutrient profile from what is listed. That could be the issue. Home cooking and feeding raw can be a very challenging project! Consulting with a vet nutritionist (ACVN) could potentially help in this situation. Another option is to use the balance website. Best of luck. 🙂

  12. Your calculation of RER is what got the obese rescue Berner I am now working on fat to begin with….it is important to note that feeding even the RER calories with no movement or exercise will result in fat as well. I have dramatically cut this dog’s calories while increasing swimming exercise to begin getting what amounts to 60-70 lbs he needs to lose in total. He has lost 30 so far this year.

  13. I forget who I first heard this weight assessment technique from, but this “touch assessment” advice works well for me to assess the weight of my own dogs and not have to go into the vet’s office frequently to get on a scale. I advise my clients to use the “touch test” for ideal dog’s weight. Ideal weight – you should be able to lightly stroke the side of your dog and easily feel rib bones, press lightly at the shoulders and top of hip / butt bones and feel the bones with only light pressure. Obviously, seeing the spine protruding and / or visually seeing a lot of rib definition is too thin. Seeing some visual of a rib bone while a smooth-coated dog is in motion, may fall into the area of “ideal weight”.

  14. Many years ago I had a cairn terrier who was overweight. I was sort of aware that Annie was too heavy but pretended to myself that she wasn’t. Then, one day when we were walking in our neighborhood, a woman who stopped to pet Annie said, “Your dog has such a cute face, and a little piggy body.” That was my wake-up call. It was time to take action. I increased the distance I walked Annie, decreased the size of her meals, and bought a digital bathroom scale so I could monitor her weight (weighing myself both while holding and not holding her). It took about a year for Annie to reach her ideal weight, which she maintained for the rest of her life. I never saw the woman again but have always been grateful to her for speaking the truth.

  15. Great article! Thanks for the calculations as well. My vet always says that my springer spaniel is about 5-10 lbs overweight. The math equation was great to see if I was feeding him correctly for his target weight. The pictures are great as well. Thank you!

  16. After a very expensive operation (twice) to repair a broken hock, I decided, along with the vet that it was time to help our Callie lose weight. It took several months being diligent and with an Exel chart to take off 10+ lbs. She is more lively and looks forward to her moring walks of a mile.
    I created the chart, listing everything she would eat during the day including what her total calories were. Nineteen Columns.
    Day, Date 2022, TIME, 3 MEALS, Purina Pro Plan Low Fat 6.7 oz = 181.6 Cal, Home-cooked Dog Food 2.5 oz = 106.3 Cal, Wet Trky. Dck. Stw 1.3 oz = 33.2 Cal, Wet Bf, Lmb, Bsn .2 oz = 31.9 Cal, Instnct Lamb Dry 1.0 oz = 123 Cal, Instinct Lamb w/wet 1.7 oz = 209.0 Cal., Pumpkin 0.4 oz = 4 Cal., Vitamin 1= 14 Cal., Treat 1 = 21.2 Cal., Pil. Pkt 23 cal,
    Blue Berry treat 1 = 6 Cal., Mlk Bone Dntl Chw 1 = 100 Cal., Benefal treat 1 = 24 Cal., MEAL TOTAL, DAY TOTAL CALORIE., WEEK DAY AVERAGE.

    I keep her at about 350 calories per meal. As you see there is a column for different foods. I switch her around so meals wont be so boring. She has been on this schedule for 74 weeks now and has been holding at 73-74 lbs. She is a standard golden doodle. I do keep a kitchen scale and use it for all three meals.
    It’s helpful to keep the time that she eats, because (we’re in our late 80’s) either my husband or I fix her meal, we know how long or short a time it was that she ate before. She has never passed up a meal and eats all of the food. Before this, we used to fix her meal and she may or may not want to eat it. We would have to cover and set it in the frig. Now she cleans her “plate”. 😊

  17. ihad my little jackpot diagnosed heart failure suddenly started thinking of losing him rwo episodes breathing heavy all day one stayed overnight i no longer let him have egg in slice of bacon use coco oil lightly to take his meds in hard yoke trying to raw diet and different kibbles sprinkle crushed mag calcium zinc d3 vit e fish oil had anti biotic to see if he would chew a bone if it was infected gums i have read that animals have ability to rejuvenate i believe it he has become happy little guy again not as energetic but close still taking meds after 1 year 150.00 month he may still have heart failure but at 7 yrs hoping to have quality of life. vet said it wouldnt happen but i changed everything he ate i think it worked out for him he wouldnt eat before now anxious for dinner.seems like a miracle to me