Is your dog showing a lower interest in playing or experiencing weight gain without you increasing their food intake or changing their diet? It may be time to have them checked for hypothyroidism.

We know what you're thinking — isn't that a human disease? Yes, but there are many common illnesses between humans and dogs, and hypothyroidism is one of them. In fact, you may notice somecommonalities in symptoms, too.

How do you know when to get your furry friend tested for hypothyroidism? Read on as we look at its signs and offer some tips on how to lower your dog's risk of illness.

Hypothyroidism is an endocrine disease that causes the thyroid gland to produce insufficient thyroid hormones. These hormones are vital in body functions like metabolism and, therefore, have a direct impact on your furry friend's energy levels and overall health.

Hypothyroidism can result from idiopathic thyroid gland atrophy or lymphocytic thyroiditis. Idiopathic thyroid gland atrophy is an illness characterized by the formation of adipose (fat) tissue where thyroid tissue should be. On the other hand, lymphocytic thyroiditis is an immune-mediated disorder that causes the immune system to attack the thyroid gland, impacting its ability to produce hormones.

While it's unclear why these conditions occur, professionals believe that some breeds may be more predisposed than others, suggesting that genetics may be responsible in some cases (more on this below).

Hypothyroidism is extremely rare for young dogs. It typically occurs among middle-aged or older dogs aged 4-10 years, with the most common ages being between 6 and 8 years. Some vets believe that the risk of occurrence increases among spayed females and neutered males, but they're unsure why.

Further, the risk is higher in medium to large breeds like:

• Golden Retrievers

• English Setter

• Benji

• Old English Sheepdog

• Boxer

• Chesapeake Bay Retriever

• Border Collie

• Cocker Spaniels

• Doberman Pinschers

• Irish Setters

• Dachshunds

This isn't to say that all smaller breeds aren't susceptible to the disease — the Maltese may be at risk, but other smaller breeds are not likely to get the illness. Again, there's no definitive answer on why some dogs have a higher risk of a hypothyroidism diagnosis, though vets believe it could result from heritable traits.

While thyroid disease is a slow-progressing illness, it does present some symptoms over time. Here are the clinical signs and symptoms of hypothyroidism to look for:

• Weight gain (noticed by both pet owners and vets): If you notice a sudden increase in weight despite maintaining your furry friend's diet and food intake, get them checked out.

• Decreased energy (first noticed by pet owners): If you have an energetic dog that suddenly starts to slow down for no apparent reason, you may want to check their thyroid.

• Hair loss or thinning/hair clipped and doesn't grow back (commonly reported by pet owners): Your dog's hair coat can become brittle and thin (especially on their back or tail) because of reduced thyroid function.

• Changes in skin coat (commonly reported to veterinarians by pet owners): Your dog may have darkened, thickened skin in areas of high pressure, including the armpit, groin and elbows.

• Heat-seeking (first noticed by pet owners): A slowed metabolism can make it difficult for dogs to maintain their body heat. So, you may notice them lying close to heat sources like heaters more often than they typically do.

• High cholesterol (veterinarian often notices this before pet owners): Hypothyroidism can reduce the body's ability to process lipids, resulting in elevated cholesterol.

• Lower heart rate (veterinarian often notices this before pet owners): This may result from a lower metabolism.

• Sad appearance (first noticed by pet owners): Reduced energy levels can make your furry friend less lively than usual and cause a tragic face.

• Larpar (change in bark): Hypothyroidism can result in a weak or hoarse bark.

• Mild anemia (veterinarians often notice this before pet owners): Signs like pale gums may hint at mild anemia, which could indicate hypothyroidism.

• Neurological manifestations: In severe cases, dogs may show signs like a lack of coordination and limb weakness.

It's worth noting that the signs and symptoms discussed above could also point to other medical conditions. Schedule an appointment with a veterinarian for a definitive diagnosis of hypothyroidism.

To distinguish between hypothyroidism and other conditions, your vet will likely conduct a physical examination and run blood tests to check your dog's total thyroxine level (Total T4 or TT4) — a low level could indicate hypothyroidism, while a high level could mean hyperthyroidism.

For cases where the results are more borderline, vets run free T4 or TSH (thyroid stimulating hormone) tests. They help differentiate hypothyroidism and reduced thyroid function resulting from conditions like diabetes.

Your dog's diet has little influence on the diagnosis or treatment of hypothyroidism.

Still, it's important to maintain a balanced diet that incorporates iodine, as an iodine deficiency can contribute to hypothyroidism. Talk to your vet to determine how much iodine to add to your dog's diet, as well as what other nutrients to incorporate.

Prevention is better than cure. While this may sound cliche, it's an important rule to live by since hypothyroidism isn't curable — it's only manageable.

Here are some ways you can minimize your dog's risk of getting sick:

Iodine is an essential nutrient for dogs, as it helps them produce thyroid hormones. This can directly impact processes like metabolism, potentially improving pet health.

Some great sources of iodine for dogs include fish, eggs, cranberries, peas and seaweed or kelp. However, eating too much of these ingredients can result in too much iodine, which may affect their thyroid function.

Consult with a veterinary professional to ensure you give your pet just enough. Depending on their hormone levels, your vet will tell you which supplements or ingredients to add and in which quantities.

While a lack of physical activity doesn’t directly cause thyroid disease, giving your dog enough exercise can improve their overall health, prevent conditions that can contribute to hypothyroidism and help them with weight loss. Here are some activities that can promote physical activity:

• Introduce daily walks or jogs for your furry friend.

• Incorporate interactive games such as tug-of-war and fetch.

• Teach them tricks that involve physical movement.

• Regularly plan playdates and visit dog parks to encourage them to interact with other dogs.

• Allow them to run around your yard.

Unlike humans, dogs' bodies aren't equipped to process sugar or highly processed products. Feeding them these foods can impact their thyroid health and overall wellness.

Avoid things like corn syrup, meat by-products and foods with artificial preservatives, and instead, choose human grade options made with whole products.

While hypothyroidism can't always be prevented, you can take proactive steps to support your dog's thyroid health. Give them enough exercise, avoid sugar and highly processed foods and keep a balanced diet to improve their physical and mental health.

With The Honest Kitchen, sustaining a healthy, balanced diet is easy. We use real, whole ingredients to make our dog food and maintain human grade standards from ingredient sourcing to food distribution, ensuring your furry friend gets the highest-quality options in the market.

Browse our dog food collection today  to promote your dog's overall health with high-quality nutrition!