Last week, we talked about the signs of hyperthyroidism in cats and possible treatments. In today’s article, you are going to learn about the possible causes of hyperthyroidism and ways to avoid this dangerous disease.
Hyperthyroidism in cats happens due to autonomously hyper-functioning nodules or benign (or, rarely, cancerous) tumors on the thyroid gland. And, as with most similar conditions, the true cause is very hard to identify, mostly because such conditions do not develop overnight.
Causes of hyperthyroidism in cats
Currently, there are several theories about potential causes of hyperthyroidism in cats. None of them have been confirmed, however, nor are they likely to be in the near future.
Fire retardants known as polybrominated diphenyl ethers, or PBDEs, are currently the trigger most suspected to cause hyperthyroidism in cats.
Why? Because its use increased heavily during the 1970s and the diagnosis of hyperthyroidism cases in cats saw a dramatic leap after 1979. It was, therefore, common sense to assume that the two events might be connected; PBDEs were already being discussed as a health hazard for humans at the time.
However, later, there was a study that analyzed the body burdens of PBDEs in hyperthyroid- and non-hyperthyroid cats, and no correlation between PBDE levels and hyperthyroidism was found. What they did find out is that levels of PBDEs are greater in cats than in humans.
The good news? THe use of PBDEs is banned in the European Union and several states in the US have also begun procedures to ban them in the future.
Canned food is also theorized to be a potential cause of hyperthyroidism in cats.
A study in 2000 suggested that cats who ate canned fish, liver, or giblet-flavored cat foods were at a higher risk of developing hyperthyroidism. The research, however, does not tell us why. So far, two theories have been offered:
#1 Polluted fish in cat food. Since cats who ate fish-flavored cat foods were found to be at risk, the blame was pointed at the fish itself. Indeed, among the animals used in the food industry, fish are the ones most polluted with heavy metals, toxins, and even the before-mentioned flame retardants. The most polluted fish are the larger ones, such as salmon and tuna – very popular flavors of canned cat food. The solution is simple: limit fish-flavored foods from your cat’s diet. They’re not on a cat’s natural menu and they can cause cats to have numerous digestion problems and nutrient deficiencies. Read more about feeding fish to your cat here.
#2 Bisphenol A (BPA) in the lining of cans. BPA is suspected cause of hyperthyroidism not only in cats, but in humans as well. It is a chemical used to make plastics and adhesive resins for lining water pipes and the inside of cans. Consequently, the BPA particles end up in the food – although the quantities don’t amount to much, how can we know if it’s safe? On a side note, not all cans use linings that contain BPA; in fact, very few cans have linings containing BPA these days.
IMPORTANT: Do not switch your cat back to dry food in fear of hyperthyroidism. Dry food raises more health concerns than can linings do. If you are worried, try using cat food from pouches or cardboard containers, or switch to a homemade raw diet.
High iodine in the diet is the suspected cause of hyperthyroidism in cats that has been suggested most recently.
However, no long-term research on this currently exists. What we do know is that low iodine levels can decrease the activity of thyroid hormones, and Hill’s Prescription Diet claims that restricting iodine intake can help improve thyroid health in cats.
There are also other theories about possible causes of hyperthyroidism in cats. They have acquired different amounts of recognition and it is likely that new theories will emerge in the future because we do not know the cause for certain. In fact, it is probably the case that a combination of many tiny things related to the environment, activity levels and diet lead to hyperthyroidism in cats.
How to avoid hyperthyroidism in your cat
While scientists are still trying to find an answer, here are a few things you can already do now to try to avoid hyperthyroidism in your cat:
- Don’t provide your cat with fish-flavored cat foods. This includes all types: canned, non-canned and raw fish.
- Don’t switch your cat to a dry diet because of a fear of canned food.
- Use a highly digestible diet: loads of protein, almost no carbohydrates. Read here how to find good commercial cat food, or switch your cat on to a homemade raw diet. Find useful information on what to include here.
- Take your cat to a veterinarian annually. Older cats should be taken to the vet twice a year and routine blood and urine tests may be beneficial. See here for other reasons to take your healthy cat to a vet.
- If any symptoms appear, take your cat to the veterinarian immediately. The symptoms may indicate hyperthyroidism or another disease – but the sooner your cat gets medical attention, the better.
As stated earlier, the actual cause of hyperthyroidism is unconfirmed and, most likely, it won’t be discovered in the near future because more long-term studies need to take place. The advice above is based on what we know so far but it doesn’t guarantee the prevention of hyperthyroidism. On the other hand, nothing can grant such a guarantee and following the suggestions here can help to reduce the risk not only of hyperthyroidism, but also of other health problems, too.