Research overview: arginine essentiality and the urea cycle in cats

Cats are exquisitely sensitive to a lack of dietary arginine, and this overview reviews why. Arginine is essential to the urea cycle that disposes of nitrogen waste from protein breakdown, and because cats have limited ability to synthesise it, a single arginine-deficient meal can cause a dangerous build-up of ammonia, with rapid, severe symptoms. Their high protein turnover makes this especially acute. Researchers demonstrated the effect through controlled feeding experiments. Why it matters: arginine essentiality is a striking illustration of how obligate carnivory leaves cats without metabolic safety nets that omnivores possess, since a meat diet reliably supplies arginine and cats never evolved to make do without it. It underscores the precision required in feline nutrition and the deep links between diet, metabolism, and survival in an obligate carnivore.