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Why is my 4-year-old dog gaining weight despite diet and exercise?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed | Female | spayed | 3 years and 9 months old | 70 lbs

My dog is almost 4 years old and very overweight. She is steadily gaining more weight each day and I'm not sure why. We feed her the appropriate amount of dog food each day and does not get very many treats. I've even tried "diet" dog food and extra exercise and nothing helps. She snores really loud, gets overheated easily, and has fast respirations

1 Answer

Most Helpful Answer

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Answered By Jennifer Summerfield, DVM CPDT-KA

Veterinarian, Certified Dog Trainer

Published on September 4th, 2018

Hi there. If you think that you're feeding Sophie a normal amount of food for a dog her size, then it's possible that she may have a medical problem such as hypothyroidism or Cushing's disease causing her to gain weight - these problems are more common in middle-aged and older dogs, but can occasionally be seen in younger pets as well. Your veterinarian can do lab work to check for these issues, and get her started on appropriate treatment if a problem is found. If her lab work shows that she's healthy, then this means she's getting more calories every day than she needs. In simple terms, this means you need to feed her less. You could do this by decreasing the amount of her regular food, or switching to a prescription weight loss diet and following the feeding instructions on the packaging based on her target weight.

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