Your cat might be sugary sweet, but we will bet that your feline friend isn’t interested in sharing your desserts. “Why?” you ask? Well, unlike every other mammal known to scientists, cats cannot taste sugar, which means that they lack a sweet tooth entirely.
There may be several different theories about why this is true, but one thing seems certain: cats have evolved from big-cat predators, and in a diet comprised entirely of meat, sugar simply wasn’t a requirement.
A Cat’s Tongue: How it Works
You probably know that the tongues of animals hold taste receptors called taste buds. These receptors detect different flavors such as sour, bitter, salty, meaty, sweet and fat. In order to taste sweet flavors, the presence of a certain receptor is required. This receptor is made up of proteins created by two genes: Tas1r2 and Tas1r3. When this sensor is present, an animal is capable of tasting sweet flavors.
Cats, however, don’t have this receptor. Over time, a cat’s tongue has evolved without a sweetness sensor, which means that not only can they not taste sweets, but they also don’t crave them.
This is most likely due to the fact that cats are carnivores, and when a diet is comprised entirely of meat, a species doesn’t need to take in large quantities of carbohydrates (often indicated by a sweet flavor) to survive.
What do Cats Taste?
Cats may not be able to taste sweets, but they can taste plenty of things that humans can’t. Humans cannot taste adenosine triphosphate (ATP), which is the compound that supplies energy for living cells, but cats can. Again, this is a result of the evolution of felines and owes largely to their all-meat diet.
The fact that cats lack a sweet receptor is interesting when you consider that some of their closest relatives, like hyenas, can detect sweets. Currently, there is some anecdotal evidence that may suggest that while the vast majority of cats cannot taste sweets, some rare individuals can. The occasional kitty that will happily enjoy ice cream or other forms of sweets evidences this. When it comes to these cats, the best scientists can figure is that they may be slowly evolving to use their Tas1r3 receptors to detect incredibly high levels of sugar.
Even if that is true in rare cases, it’s not ideal that cats consume sugar. Cats are carnivores, and as such, their systems aren’t designed to process high levels of sugar. That said, it’s important that pet parents seek out food that caters to their cat’s need for meat protein. Many cat food brands on the market contain up to 20% carbohydrates, which are difficult for a cat to digest and could be a contributing factor in developing diabetes.
It’s relatively unlikely that your cat will want to finish what’s left of your cake, but it’s obvious that cats aren’t designed to process sugar like the rest of the mammalian world. As such, pet parents who want to provide the best possible care for their feline companions should look for food that offers low carbohydrate levels for easier digestibility and better nutrition. Your veterinarian will be able to offer advice on the best diet for your cat.
Content reviewed by a veterinarian.