Our Smokey Point vets often see dogs with hypothyroidism suffering from unexplained weight gain, skin and coat issues, reduced energy and other behavioral changes. Below, we discuss this condition in more detail and how diet can be used to help treat the symptoms of hypothyroidism in dogs.


Hypothyroidism is a condition that occurs when your pup's thyroid isn't producing enough essential thyroid hormones to properly regulate their metabolism, causing the metabolism to slow.

Causes of Hypothyroidism in Dogs

The vast majority of cases of hypothyroidism in dogs are caused by either lymphocytic thyroiditis or idiopathic atrophy of the thyroid gland. While these conditions are poorly understood both result in damage to the dog's thyroid. In the case of lymphocytic thyroiditis the dog's own immune system attacks the thyroid, whereas with idiopathic thyroid gland atrophy thyroid tissue is replaced by fat.

There are a number of claims that hypothyroidism may be caused by external factors such as a raw food diet, standard commercial dog food diet, vaccines, lawn chemicals, choke collars, environmental toxins, phthalates in dog chew toys, PCBs, and antibacterial agents in soaps. The theories behind most of these claims are based on the fact that each of these factors is believed to affect the thyroid and endocrine system in different ways. That said, further studies need to be done before any strong conclusions can be drawn.

Signs That Your Dog May Have Hypothyroidism

Because hypothyroidism causes your pet's metabolism to slow almost every organ in your pup's body is affected by the disease. If your pooch is suffering from hypothyroidism you may notice one or more of the following symptoms:

  • Unexplained weight gain
  • Obesity
  • Lack of energy, lethargy
  • Mental dullness
  • Cold intolerance
  • Thinning coat
  • Dull looking fur
  • Dark pigmentation of the skin
  • Recurring ear infections
  • Recurring skin infections
  • High cholesterol
  • Slow heart rate
  • Lameness
  • Lack of coordination
  • Thickening of skin
  • Reproductive issues

If your dog is displaying any of the symptoms listed above they may be experiencing the effects of hypothyroidism. Contact your vet to book an appointment for your dog.

If your vet suspects that your dog has hypothyroidism they will do a full physical examination of your dog and run a series of blood tests to check your pup's levels of thyroid hormones T4 and T3. There are other conditions that mimic the symptoms of hypothyroidism, meaning that diagnostic testing may be fairly extensive in order to get a definitive diagnosis.

Treatment for Hypothyroidism in Dogs

If your pooch is diagnosed with hypothyroidism treatment will likely include a prescription for the synthetic thyroid hormone levothyroxine (L-T4). It's important to note that it can take some time for your pet's hormone levels to reach just the right level, and regular blood tests may be required in order to monitor your dog's treatment progress. Once the hormone levels are stabilized your dog will remain on this prescription for life.

The Best Diet for Dogs With Hypothyroidism

In dogs with hypothyroidism, a combination of a healthy diet and hormone replacement medication can help to get your dog feeling like their old self again. Your vet will be sure to provide you with instructions for the best food to feed your dog with hypothyroidism. If you'd like to look into more detailed dietary guidelines for your dog, have your vet recommend a pet nutritionist or holistic vet near you. 

Dogs with hypothyroidism need to eat a healthy diet that includes balanced levels of amino acids, iodine, vitamins, minerals, probiotics, antioxidants, proteins, fats and carbohydrates. Your veterinary professional will be able to recommend the best diet for your dog based on your pet's precise needs.

In some cases, a homemade food may be recommended. If that's the case for your dog the vet will be sure to provide you recipes that will provide your pooch with all the nutrition they need in just the right balance.

Your vet may recommend a prescription therapeutic dog food as part of your pup's hypothyroid treatment. These diets are specially formulated to meet your pet's nutritional needs but with lower fat content.

There are a number of fresh vegetables that may help to support thyroid function which you may want to include in your pet's diet in small amounts such as asparagus, green beans, beets, broccoli, brussels sprouts, carrots, celery, lettuce, mushrooms, and spinach. But always be sure to check with your veterinarian before adding new foods to your dog's diet.

Foods to Avoid When Your Dog Has Hypothyroidism

Some vets recommend avoiding commercial dry foods for dogs with hypothyroidism, while others believe that it is best to avoid a raw food diet. When it comes to feeding your dog it is always best to seek the advice of a trained veterinary professional.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

Do you think that your dog may be suffering from hypothyroidism? Contact our Smokey Point vets today to book an examination for your four-legged friend.