I have invested the last 10 years of my life in pet nutrition but, after recent events, I have been extra careful to specifically research what is good for my cats – no longer just taking someone’s word for it. And soy is… well, let’s just say, something to look at.

So… Can Cats Have Soy?

I’ve just completed some deep research from the top experts in pet nutrition and looked at several different opinions from vets and doctors around the world to come to the following conclusion – I will never again feed my cats soy. In fact, I am physically upset that I ever did. Here’s why…

In short, soy is a cheap way of getting a quick result. Because it offers what appears to be the ‘benefits’ of amino acids, folic acid, fiber, protein and antioxidant properties, many have ruled this ingredient as healthy and acceptable in pet foods and supplements. Because of these qualities, it is easy to see a boost in energy levels, increased joint function and even decreased inflammation when using soy products. But if you research further you find a deeper issue.

Despite the benefits that soy can provide, it is just too risky an ingredient. No matter where it was grown, soy contains phytates (50-cent word) that stops the absorptions of minerals and can block enzymes needed to digest protein. In cats, this often causes liver damage or failure. Studies have shown that the effects of soy on the liver can be so harsh that it can actually be fatal in felines – even the size of cheetahs.

Now I understand why Scotch’s liver levels have been off, even though we give him the best diet available.

According to my research, soy also causes hyperthyroidism (over-active thyroid) in cats with symptoms like weight loss, voracious appetite, rapid heart rate, and behavior issues like vocalization and urinating outside the litter box.

I’m sorry to say that I’m finding this information out too late for our poor Mama girl who passed away in February from a tumor in her digestive tract that appeared to be connected to an overactive thyroid as well…

Now I’m crying.

Soy is such a controversial issue these days and, over the past several years, we were taught that soy was healthy for us and our animals… Thus, we chose the pro-soy route. Maybe it isn’t that harmful for humans. Maybe it isn’t as harmful for other animals… All I know is that I did the research on the effects it has on cats. I consulted the professionals. I read the studies. And I immediately threw away all soy supplements that we had been giving them. I pray that the damage that’s been done can be reversed by using absorbable supplements that are higher in quality and contain no soy.


Soy-Free Product Recommended For Your Cat


CATalyst Antioxidant Enzyme Formula – 2 oz



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