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6 Best Cat Foods for Hyperthyroidism – Reviews & Top Picks

cat eating dry and wet cat food

Hyperthyroidism is a serious condition that negatively impacts a cat’s health. Unfortunately, it is the most common endocrine disorder in older cats and has been known to occur in about 10% of cats that are 10 years or older. The more common symptoms are an increase in thirst, urination, and appetite, as well as weight loss.

If you know that your cat has hyperthyroidism, you probably have already seen your vet in order to have this disease properly treated. Treatment usually includes an adjustment to your cat’s diet, medication, radioactive iodine therapy, or surgery. The most important part of a diet for a cat with hyperthyroidism is food that is low in iodine. Restricting iodine in a cat’s diet will help reduce the thyroid from overproducing the thyroid hormone, thyroxine, which causes hyperthyroidism.

The following reviews include dietary treatment products with little to no iodine that can be fed exclusively to your cat. We also include some high protein options that might benefit a cat after radioactive therapy treatment if it is not diagnosed with kidney disease.

Important: Your veterinarian’s advice is essential, especially if your cat has a medical condition. Never change the diet of your cat suffering from hyperthyroidism, without your veterinarian’s authorization. 

divider-pawA Quick Comparison of Our Favorites in 2022

Image Product Details
Best Overall Dietary Treatment
Winner
Hill’s Prescription Diet Thyroid Care Cat Food Hill’s Prescription Diet Thyroid Care Cat Food
  • Only canned food for cats with hyperthyroidism
  • Clinically proven to benefit thyroid health in 3 weeks Low in sodium and phosphorus for kidney health
  • Omega-3 and -6 for healthy coat and skin
  • Best Valaue Dietary Treatment
    Second place
    Hill’s Prescription Diet Thyroid Care Dry Cat Food Hill’s Prescription Diet Thyroid Care Dry Cat Food
  • Specifically meant to help cats with hyperthyroidism
  • Regulates tyroid activity
  • Supports heart, kidney, and urinary health
  • High Protein Post Radioactive Therapy Option
    Third place
    Wellness Complete Health Cat Food Wellness Complete Health Cat Food
  • Three different sized cans
  • Chicken is the main ingredient and is grain-free
  • Antioxidants and omegas for immune system and healthy skin and coat
  • High Protein Post Radioactive Therapy Option
    Instinct Original Grain-Free Cat Food Instinct Original Grain-Free Cat Food
  • Comes in two sizes, cans are BPA free, and pâté is grain-free
  • First three ingredients are whole meats
  • Doesn’t contain by-products, corn, wheat, grain, artificial preservatives or colors
  • High Protein Post Radioactive Therapy Option
    Instinct Limited Ingredient Cat Food Instinct Limited Ingredient Cat Food
  • Limited ingredients for cats with food sensitivities
  • Doesn’t contain grains, dairy, eggs, artificial colors, or preservatives
  • Natural antioxidants and omegas for the immune system, coat, and skin health
  • The 6 Best Cat Foods for Hyperthyroidism

    1. Hill’s Prescription Diet y/d Thyroid Care Cat Food — Best Overall Dietary Treatment

    Hill’s Prescription Diet y:d Thyroid Care Cat Food

    Flavor: Chicken
    Food texture: Pâté
    Protein: 8%
    Size: 5-oz. x 24

    The best overall canned food for hyperthyroid cats is Hill’s Prescription Diet y/d Thyroid Care Cat Food. This is the only canned food made specifically to help cats with hyperthyroidism, and it is available in a case of 24 cans that are 5.5 ounces each. It has been clinically proven that this Thyroid Care food will restore thyroid health in as little as 3 weeks. Since thyroid issues usually happen to older cats, kidney damage is another concern, and this food is also low in phosphorus and sodium, which will help with kidney health. It contains omega-3 and -6 for healthy skin and coat and added taurine and carnitine for a healthy heart and weight.

    On the downside, it is expensive, and it contains pork by-products and corn flour. You’ll also need a vet prescription for this cat food.

    Pros
    • Only canned food for cats with hyperthyroidism
    • Clinically proven to benefit thyroid health in 3 weeks
    • Low in sodium and phosphorus for kidney health
    • Omega-3 and -6 for healthy coat and skin
    • Taurine and carnitine for heart health and weight
    Cons
    • Expensive
    • Contains corn flour and pork by-products

    2. Hill’s Prescription Diet y/d Thyroid Care Cat Food — Best Value Dietary Treatment

    Hill’s Prescription Diet y:d Thyroid Care Cat Food dry

    Flavor: Chicken
    Food texture: Dry
    Protein: 30%
    Size: 4 and 8.5 lbs.

    Our pick for best value dietary treatment for cats with hyperthyroidism is Hill’s Prescription Diet y/d Thyroid Care Cat Food. This dry food is explicitly designed to help cats with hyperthyroidism and is proven to improve thyroid health in three weeks. It decreases the T4 hormone production and helps support urinary, heart, and kidney health. It also aids in a healthy immune system and a healthy coat and skin.

    However, it is still quite expensive, and the ingredients aren’t the greatest. In fact, corn gluten meal is listed as the first and therefore, the main ingredient, which is strange, to say the least. But the food works.

    Pros
    • Specifically meant to help cats with hyperthyroidism
    • Regulates thyroid activity
    • Supports heart, kidney, and urinary health
    • Aids in a healthy immune system and skin and coat
    Cons
    • Expensive
    • Corn gluten meal is the main ingredient

    3. Wellness Complete Health Canned Cat Food – High Protein Post Radioactive Therapy Option

    Wellness Complete Health Cat Food

    Flavor: Chicken
    Food texture: Pâté
    Protein: 10.5%
    Size: 3-oz. x 24, 5.5-oz. x 24, 12.5-oz. x 12

    The best cat food for the money for cats with hyperthyroidism is Wellness Complete Health Cat Food. Now, this food isn’t super cheap, but when you have a cat with such a serious health condition, you do need to pay more to keep them in optimal health. This pâté is available in three different sized cans and is grain-free, with chicken as the main ingredient. It’s full of omegas and antioxidants for immune system support and healthy skin and coat.

    On the downside, some cats might not want to eat it (we know how picky felines are!), and on occasion, the food has a thicker and drier texture that some cats might also find off-putting.

    Pros
    • Three different sized cans
    • Chicken is the main ingredient and is grain-free
    • Antioxidants and omegas for immune system and healthy skin and coat
    Cons
    • Some cats won’t eat it
    • Texture might be dry and thick

    4. Instinct Original Grain-Free Pate Canned Cat Food – High Protein Post Radioactive Therapy Option

    Instinct Original Grain-Free Cat Food

    Flavor: Chicken
    Food texture: Pâté
    Protein: 10%
    Size: 3-oz. x 24, 5.5-oz. x 12

    Instinct’s Original Grain-Free Cat Food is a pâté that comes in two sizes and is grain-free. The first three ingredients are whole meats, including chicken, turkey, and chicken liver, which can help build your cat’s muscles. It doesn’t contain any animal by-products, grain, wheat, corn, or artificial preservatives or colors. It has omega fatty acids to improve your cat’s skin and coat, and the cans are BPA-free.

    The disadvantage is that the texture of this food is also quite loose and almost runny, which may or not be a bad thing.

    Pros
    • Comes in two sizes, cans are BPA free, and pâté is grain-free
    • First three ingredients are whole meats
    • Doesn’t contain by-products, corn, wheat, grain, artificial preservatives, or colors
    • Omega fatty acids for healthy coat and skin
    Cons
    • Pâté is on the runny side

    5. Instinct Limited Ingredient Diet Rabbit Dry Cat Food – High Protein Post Radioactive Therapy Option

    Instinct Limited Ingredient Cat Food (1)

    Flavor: Rabbit
    Food texture: Dry
    Protein: 35%
    Size: 5 and 10 lbs.

    Instinct’s Limited Ingredient Cat Food comes in two sizes and has limited ingredients, which also works for cats with food sensitivities. It is only made with one animal protein (rabbit) that is freeze-dried, and it doesn’t contain any grains, dairy, eggs, fish, wheat, or artificial preservatives or colors. It does have natural antioxidants and omegas to boost the immune system and the skin and coat.

    However, some cats might experience stomach upset after eating this food, and it does tend to be rather smelly. Also, the food is quite dark in color — almost black — but this is normal because it has a raw coating.

    Pros
    • Limited ingredients for cats with food sensitivities
    • Doesn’t contain grains, dairy, eggs, artificial colors, or preservatives
    • Natural antioxidants and omegas for the immune system, coat, and skin health
    Cons
    • Some cats might experience stomach upset
    • The food is rather smelly

    6. Stella & Chewy’s Freeze-Dried Raw Cat Food – High Protein Post Radioactive Therapy Option

    Stella & Chewy’s Freeze-Dried Raw Cat Food

    Flavor: Chicken
    Food texture: Freeze-dried morsels
    Protein: 45%
    Size: 5 oz., 8 oz., 18 oz.

    Stella & Chewy’s Freeze-Dried Raw Cat Food is high in protein because it’s raw food but conveniently freeze-dried to help preserve the nutrition. You can feed it as is to your cat or rehydrate it with water. This food is made in the U.S. and contains only organic fruits and vegetables. It doesn’t contain any fillers, gluten, grains, or artificial flavors or colors.

    On the negative side, it is expensive, and some cats might not want to eat it. You might also find that the morsels are big for a small cat.

    Pros
    • High in protein
    • Raw food that is freeze-dried to preserve nutrition
    • Doesn’t contain fillers, gluten, grains, or artificial flavors, or colors
    • Only includes organic fruits and vegetables
    Cons
    • Expensive
    • The morsels are big

    divider-cat

    Buyer’s Guide: Selecting The Best Cat Foods for Hyperthyroidism

    We have a few more things for you to consider before you make your first purchase of a new cat food. It’s best to be well-informed, particularly because this kind of food is expensive, so you’ll want to consider every aspect beforehand.

    cat eating food from a bowl
    Image Credit: Viktor Lugovskoy, Shutterstock

    Cat Food Ingredients

    This is the most essential part of choosing food for your cat. If you want to give your cat food that does not contain iodine or at least a reduced amount, it’s important to know what ingredients naturally have iodine:

    Seafood: Fish, shrimp, seaweed
    Dairy products: Yogurt, cheese, milk
    Egg: Mainly yolks
    Salt: Iodized table salt

    So, before you purchase your cat food, always read the ingredients list first. Check that the ingredients containing iodine are minimal or not included and that the first three to five ingredients should be whole meat whenever possible.

    Most foods don’t list the amount of iodine contained, so you’ll want to contact the manufacturer or look through reviews to find out this information. In general, it is recommended that your cat’s food should contain less than 0.32 ppm of iodine to be on the safe side, only products number one and two in this list stay under that limit, thus they are considered dietary treatments.

    Of course, if your cat doesn’t like chicken or has a food sensitivity to it, you’ll want to look for different flavors.

    The Best Cat Diet

    Cats with hyperthyroidism should have a diet with 5–10 % carbohydrates, 50–70% protein, and 30–40% fat. Generally speaking, a diet that is high in protein and low in carbohydrates and has a moderate amount of fat is what you need to be looking for.

    Since cats with hyperthyroidism tend to lose weight, they need the extra protein and fat to help them put on weight and to contribute to a healthy coat. A cat with hyperthyroidism tends to have a rather ratty-looking coat.

    It’s a balancing act because older cats might have other issues beyond hyperthyroidism, such as diabetes or kidney disease. It’s thought that canned food is better than dry for the extra water content.

    Both radioactive therapy and surgery cure hyperthyroidism and feeding a high protein diet can help a cat recover the muscle and weight lost during the disease process. However, it is fairly common for cats to be diagnosed with renal disease after radioactive therapy. This happens because hyperthyroidism was masking the diagnostic markers of renal disease on the cat’s blood samples, once the hypothyroidism is resolved, the renal disease becomes evident in the blood parameters. High protein diets are contraindicated for renal disease and the cat will need a different dietary approach. This is why it is very important to follow up with your veterinarian to find out what is the best diet specifically for your cat’s case and condition. Each cat is unique and feeding the right diet will make a huge difference in their health.  cat eats from a plate with wet cat food

    Image Credit: correct pictures, Shutterstock

    Dietary Treatments and Multiple Pets

    Always speak to your vet about your cat’s diet and possible choices in food before you purchase anything. If you will try a dietary treatment, it’s important to note that once you’ve put your cat on a special prescription diet to treat their hyperthyroidism, you shouldn’t feed them anything else — no treats and no other food.

    Some of these special foods, particularly the prescription ones, are only meant for cats with hyperthyroidism. If you have other pets in the house that like to eat your cat’s food, you’ll need to find a way to feed your cat and prevent the rest of the animals from eating it, and vice-versa.

    Giving your pet the highest quality nutrition is a top priority, so why not give them a food and water dish to match? We think the Hepper Nom Nom Bowl is too good not to share.

    Made from food-safe stainless steel, you can ensure that your pet is consuming the best nutrition out of the finest bowls on the market. Click here to get yours.

    At Pet Keen, we’ve admired Hepper for many years and decided to take a controlling ownership interest so that we could benefit from the outstanding designs of this cool cat company!

    divider-pawConclusion

    If you’re on the lookout for the best overall cat food to help with your cat’s hyperthyroid, Hill’s Prescription Diet y/d Thyroid Care Cat Food is the best bet for dietary treatment because it’s specially designed for this condition. You’ll need to speak to your veterinarian about the best value dietary treatment option Hill’s Prescription Diet y/d Thyroid Care Cat Food. It’s expensive but very effective!

    Wellness Complete Health Cat Food is a better good high protein choice for a cat that is recovering from radioactive therapy treatment and has not been diagnosed with kidney disease.

    We hope that our reviews will help you to be informed and know about the different options of food for your cat. Hopefully, the right diet, medication, or treatment will see your cat get back to optimal health as soon as possible.


    Featured Image Credit: Nils Jacobi, shutterstock

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