Feeding My Hyperthyroid Cat
The best diet for your hyperthyroid cat satisfies his/her nutritional requirements as an aging carnivore recovering from a muscle-wasting disease, and avoids chemicals that may contribute to thyroid disease. We encourage you to read cat food labels and consider these guidelines.
It is best to feed:

Canned or raw diets, that contain little to no fruits, vegetables, or grains. Any canned cat food is better than most dry options, which contain too much plant-based protein and carbohydrates. Meat by-products are fine for carnivores; they are simply protein sources such as organ meats and entrails that people do not find appetizing. Gravy foods tend to be high in carbohydrates, so patés are a better choice.
Motivated clients may check out the website, which gives nutrient breakdown of various prescription and over-the-counter diets in the link “Protein/Fat/Carbs Chart”. It turns out that many of the OTC canned diets have an acceptable composition of these, and are reasonably low in phosphate, i.e.:
- >40% meat protein (>12g/100 kcal)
- <10 % carbohydrates
- 50 % fat
- <250 mg/100kcal phosphate
Note: these percentages are based on dry matter, metabolizable energy, unlike those on the can label.
It may be best to avoid:
- SOY-containing foods
- BPA in canned food linings
- Plastic food and water bowls (replace with glass, ceramic or metal)
- Storing food in plastic containers
- Ultra-high or ultra low iodine diets
- y/d® diet, Hills®
Note: All hyperthyroid cats need to eat as much as they possibly can*. Offer food ad lib, and if you have a cat, heavy or thin, that refuses new diets, stick with what they will eat best. Sometimes gradually transitioning them from less-than-optimal diets to more nutritionally suitable ones works.
*If your cat is overweight, we do not recommend unrestricted calories, even before treatment here. However, we do still recommend to switch your cat to a fully wet/canned diet. Consult with your primary veterinarian about specific diet and amounts to feed.
Testimonials
Ripley (kitty) and I just wanted to thank Dr Vaughan and the whole staff for your great service and care. You were all great to work with, and communicated well with us! Ripley left... read more
Kali & RipleyWe want to thank you for your extraordinary efforts in looking after our Samson's well being. You took the initiative of a problem we were not aware was even present. We are very, very... read more
SamsonPort Townsend, WA
My cat was diagnosed as hyperthyroid when she was 10. We had her treated as soon as she was diagnosed and I was glad it was found early. I didn’t really give the thyroid... read more
SavannahLynnwood, WA
Princess started losing weight and after checking with the vet she was confirmed as being Hyperthyroid. After Approximately 13 months of of a paste-like med applied to the ears, switching from left to right... read more
Great place. They were so good to my kitty who was really scared. He seems to be completely cured. read more
Monty is 12 years old. Dr. Vaughan had been monitoring Monty’s thyroid over the years and identified that he was borderline for hyperthyroidism. After discussing his overall appearance, behavior and appetite, we decided that... read more
MontyMy family has had Lila since she was a kitten. She is turning 15 in October, I was only 10 when we got her. I moved away as an adult for a few years... read more
LilaShoreline, WA
Thanks to Dr Faythe Vaughan, and her kind staff in Shoreline and Tacoma for giving us at least 5 extra, good quality, years with our buddy, Rocky! He was a rescue cat to begin with, and his good... read more
RockyTacoma, WA
As a member of an animal rescue organization on Vashon Island (VIPP), as well as being a chronic cat owner, I've had many opportunities to visit the Feline Hyperthyroid Treatment Center. Over the past... read more
Piro Kramar. Vashon Island Pet ProtectorsVashon Island, WA
Hello! Just wanted to let you know Rio Blanco is doing great! As soon as we got home he started emptying the bowls of food! I haven't even opened the anti-nausea or the... read more
Patrick and RioThree months ago my 13 year old kitty Miss Fanny spent three days in the care of Dr. Vaughan and the staff. Before treatment she had been losing weight, getting more lethargic and her... read more
Miss FannyNorthbend, WA
I wanted to drop you and everyone at FHTC a note to let you know that Byron (the PAWS™ kitty FHTC treated pro bono earlier this year) was adopted last month! Even better, he... read more
ByronSeattle, WA
Pox's Story Does it make sense to treat hyperthyroid in a fourteen-year-old, mostly outdoor cat? That’s what we were asking ourselves in the summer of 2013. Pox let me know his opinion by following me... read more
PoxSeattle, WA
You took care of our Nina Kitty and it was like she found the Fountain of Youth! At age twelve, she had been slowly losing weight and getting a bit more "yowly" but we... read more
NinaWill & Grace found me in 1999 when they were four weeks old. They were born near in a parking lot off Highway 99. They are twins and do everything together. This year they celebrated their... read more
Will, Grace, and HunterEdmonds, WA
Dr. Vaughan; Kathy; Miranda; and anyone who was involved in treating and caring for Tigger. Just wanted you to see the life Tigger is leading because of your excellent care on this upcoming anniversary... read more
PepperThey are very personable, professional, and knowledgeable about their very specialized practice. If you have a cat with thyroid issues, I highly recommend this clinic. read more
BeckySeattle, WA