If your dog has been diagnosed with an underactive thyroid then you are probably looking at all the ways that you can help to support them. Hypothyroidism is a condition that is usually managed with long-term medication, but the right nutrition is also important. Let’s explore what hypothyroidism is as well as look at some nutritional dos and don’ts.

Table of contents

What is hypothyroidism?

Hypothyroidism is a condition where not enough thyroid hormones (T3 and T4) are being produced by your dog’s thyroid glands. These glands are found in the neck and produce hormones to control your dog’s metabolism. If they are underactive then not enough T3 and T4 are produced which can have widespread effects on the body. This is different to hyperthyroidism, a condition more common in cats, where an excessive amount of hormones is produced.

The causes of hypothyroidism in dogs are not well understood, but 95% of cases are caused by the destruction of the thyroid gland. The two main diseases that cause this condition are lymphocytic thyroiditis (an immune-mediated condition where the body attacks its own cells) and idiopathic gland atrophy (normal thyroid tissue becomes replaced by fat). Genetics are thought to play a part, however, with lymphocytic thyroiditis having a hereditary component. Either way, the treatment is still the same.

What are the symptoms of hypothyroidism?

The symptoms of hypothyroidism are wide-ranging, as a slowing of the metabolism affects all the organs in the body. The most common symptoms seen are as follows–

  • Unexplained weight gain
  • Lethargy
  • Not wanting to exercise as much as normal, or struggling to keep up on a walk
  • Dull coat condition
  • Excessive fur loss, especially on your dog’s sides, neck and tail
  • Dry, flaky skin
  • Skin pigmentation (skin may look darker than normal)
  • More frequent skin or ear infections
  • Feeling more cold than usual (shivering)
  • Slow heart rate
  • Thickening of facial skin leading to a sad facial expression
  • Fertility issues

How is hypothyroidism treated?

If your vet suspects hypothyroidism then they will take some blood samples. Your vet will usually run a general profile to check your dog’s overall health but will also run panels that specifically check their thyroid hormones.

If the condition is diagnosed, it is not curable but can be managed through long-term medication. This oral medication contains a synthetic thyroid hormone replacement which needs to be given every day. Regular blood tests and checkups are needed to make sure that dosing is correct.

However, in addition to their medication, it is worth looking at your dog’s diet, to help support them further.

The dos and don’ts of feeding your hypothyroid dog

Nutrition is a big part of our pet’s health. While there is no specific diet for dogs with an underactive thyroid, here are a few general dos and don’ts which might be helpful –

Do:

Look at a calorie-controlled regime

If your dog is overweight, then you may need to start them on a weight reduction regime. This includes choosing a diet that is lower in calories and cutting back on any treats or table scraps too.

Weigh their food out properly

Weighing your pet’s food out each day is important, as it can be easy to accidentally overfeed them. Using scales will be more accurate than using your hands or a cup.

Choose a diet that supports skin health with added EFAs

Diets that have added essential fatty acids (EFAs) can help to support your dog’s skin and coat condition, which can be poor with hypothyroidism. You could even consider using an EFA supplement.

Do ask your vet for their recommendations

Always speak to your vet for their diet advice. They will also be able to support you if your dog needs to lose weight, as this needs to be done safely and without causing your dog to become excessively hungry.

Don’t

Stop giving your dog their medication

Don’t make the mistake of thinking that you can control your dog’s condition through diet alone; they will need to continue their medication long-term.

Give your dog a home-cooked diet

The only exception to this is if you are working alongside a qualified veterinary nutritionist. It is easy to get nutrient levels wrong when feeding a home-cooked diet, which could accidentally make things worse.

Supplement your dog’s diet with iodine

Iodine is essential for the production of thyroid hormones, so naturally, you might think that adding more iodine to your dog’s diet will help. However, commercial diets already contain adequate amounts of this nutrient. As such, most dogs don’t have an issue with iodine deficiency, and their problem is caused by a functional problem of the gland itself. Giving your dog more iodine is not helpful and could cause other issues.

Summary

Hypothyroidism is a condition that requires long-term medication to control. Your vet will need to monitor your dog with regular blood tests to ensure that their hormone levels are correct. While there is no specific diet for dogs with hypothyroidism, hopefully, our list of dos and don’ts will give you a few pointers when thinking about your pet’s diet generally.

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