My cat has an over-active, swollen thyroid, causing him to constantly be hungry, and frequent vomiting. So, out of four options - radiation treatment, surgery, daily tablets, or a changed diet - we chose to give him a changed diet, with no iodine which the thyroid needs to function apparently. However, the batch of non-iodine foods were usually not eaten by our cat, so instead a family member decided to give him 100% natural (packaged) meat food instead (which predictably were met with favour from our cat).

I, however, am concerned having read that meat may contain iodine (http://www.ncbi.nlm.nih.gov/pubmed/7216884, http://www.healthboards.com/boards/thyroid-disorders/423636-iodine-meats.html), that it is not a suitable replacement and in fact may be contributing to the functioning of the thyroid.

So, can I safely be using natural meat food instead of prescribed non-iodine food?

  • Doesn't too little iodine lead to hypothyroid and too much hyperthyroid? They have a cat with hyperthyroid and are attempting to reduce the activity via diminished iodine. My understanding is this is a theoretical possibility but at the same time it is more difficult than a medicinal titration of the thyroid
    – Dan S
    Jul 9, 2014 at 22:30
  • @DanS - Yes hyper is caused by too much, hypo by too little. Over treating hyperthyroid issues can actually lead to hypothyroid issues though. I realize my late night comment on the question conjoined them... sigh
    – Joanne C
    Jul 9, 2014 at 23:15
  • Sorry is there a point that is to be brought out? Are you saying that the cat needs a small amount of iodine? Not sure why prior comments were deleted... Jul 10, 2014 at 21:49
  • @MarcoScannadinari I didn't delete them but I guess they were deleted because they were unintentionally misleading. They implied hyperthyroid could happen from too much or too little iodine but the John meant too much iodine can cause hyperthyroid and too little can cause hypothyroid
    – Dan S
    Jul 11, 2014 at 3:34
  • 1
    As John Cavan said in his answer, that's up to your vet. It's just difficult to manage.
    – Zaralynda
    Jul 11, 2014 at 17:17

3 Answers 3


Diet management of iodine intake for your cat is going to be very difficult with food intended for human consumption. For one, much of that food has iodine in it either naturally or via addition. For example much of the salt we get is iodized precisely to help with thyroid issues in humans and it also occurs naturally in a number of meat products we consume.

If your vet is comfortable with the diet management being viable, then I think I would stick with the prescribed diet, but then you might want to gradually transition him to it rather than applying an abrupt change and while doing that transition use medication to control the thyroid until the diet transition is complete. I think you may find that model much more successful in the long run.

As an aside, there are surgical options as well as the radiation treatment Dan mentions. According to Merck, a thyroidectomy is effective in treatment and felines do not usually require a thyroxine supplement. You may want to raise that option (and get a cost) from your vet as well. Not all cats can be operated on, sedation can be a problem, but worth checking on.


"Natural meat" probably has enough iodine in it that you can't use it. Most mammals need good amounts of iodine and their body tissues (not just the thyroid) will have that... you would need to feed your cat something good which has had the iodine removed from it (not a cheap process and not foolproof either I'm sure some iodine still is present)

I'd advise you to think about radiation treatment again.

My opinion is that it is the safest and easiest option.

Titrating the thyroid (medicine) typically means a vastly shorter lifespan as the titration is seldom right.

Surgery has possible complications.

Iodine free diet is possible but hard to do (you have to always make sure they don't get iodine and that isn't easy).

The places that do radiation treatment, sure they rip you off but it is cheaper than surgery or (in the long run medicine), and it seems the safest and most surefire way of treating them problem. I've had two cats who were treated with radiation. I've known other cats treated in other ways and was not happy about those outcomes.

  • I should have mentioned that he is around 14 years old - near to the average lifespan of cats, so a substantial investment may not be worth it (as heartless as it sounds), though I will consider your answer's suggestions... Jul 9, 2014 at 10:31
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    My youngest cat is 16, my current oldest is 18 and last summer I had one who was 22. I'd avoid treatment only if you really know your cat isn't going to last (regardless) long.
    – Dan S
    Jul 9, 2014 at 10:49

Science Hills now do a dry and wet food diet that is iodine-free, it's called y/d.

My oldest cat is 17 and has had thyroid problems for almost two years. How old is your cat? Just recently, the vet advised that my cat be transferred from the vidalta tablets on to the Science Hills diet, but after some research I decided that I'd rather stick with what I know and what he knows. He has lost lots of weight recently. He eats lots of chicken and fish, which apparently are loaded with iodine (especially fish). If you attempt treating it by just an iodine-free diet, you will need to be ever so careful (advice from my vet).

Have you considered daily tablets? I have a prescription from the vet and buy them cheaper online. Hope you find something that suits your cat soon.

  • Thanks, though the "non-iodine" foods were in fact hill's y/d, which he is not eating. We have tried to give him tablets but he would constantly struggle and bite which made that impossible. He is about 14 years old Jul 15, 2014 at 15:41
  • I have read similar stories about this food and did not want to risk feeding it to my cat, even with pressure from the vet. When it comes to giving my cat anything, he freaks out and really doesn't like it so that was impossible. What we do is put it in his food. You can hide it in a piece of meat or sometimes my cat will even lap it up with biscuits. You could also try butter or marmite but both are quite salty.
    – Lucidize
    Jul 15, 2014 at 15:51
  • I don't think we can apply that to this food since it is meant to be feed exclusively by itself Jul 15, 2014 at 15:57
  • Sorry I meant to say that we hide the tablet in his food (crucial missing word)
    – Lucidize
    Jul 15, 2014 at 15:59
  • To clarify, I do not feed my cat this y/d diet.
    – Lucidize
    Jul 15, 2014 at 16:02

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