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Michael: Cats love to do things they’re not supposed to do, from jumping on counters to scratching up your couch. And yeah, that stuff is annoying, but most of the time, it’s not that big a deal. In some cases, though, a cat’s behavior can have serious consequences for their health. Like if they get into your liquor cabinet, or your toothpaste. Or even if they start shedding a lot.

Cats are curious and adorable, and the idea of a drunk cat might sound even funnier and cuter, but alcohol is incredibly dangerous for cats. Like in humans, alcohol in cats can cause decreased coordination, difficulty breathing, comas, or even death, among other symptoms. But cats are tiny compared to humans, so it doesn't take much alcohol to negatively affect them.

A few spoonfuls of whiskey might not seem like much to a full-grown human, but to a 4 or 5 kilogram cat, that’s a LOT, and might be enough to cause a coma. So even though there are lots of videos of people laughing at their cats stumbling around after ingesting alcohol, it’s probably not a good idea to let your cat taste some booze. It’s just too easy for them to wind up drinking too much.

Another item on the list of forbidden foods and drinks for cats is something that’s actually good for humans: toothpaste. Maybe you’ve heard from your vet that dental hygiene is important for a cat’s health, so you should brush their teeth. And that’s true! But it doesn’t mean you should share your toothpaste with little Simba.

Toothpaste, along with sugar free gum and mints, often contains a sweetening ingredient called xylitol that’s been found to be extremely toxic to both dogs and cats. Xylitol poisoning has been better studied in dogs, since dogs are more likely to eat sweet things that they aren’t supposed to. But it’s a problem for cats too. Even though dogs and cats can safely eat other sweeteners, like aspartame and sucralose, they can’t handle xylitol.

When dogs and cats ingest xylitol, it’s not processed the way it is in humans. Instead, it leads to an increase in insulin — up to six times as much for an equal amount of actual sugar. All that extra insulin can cause hypoglycemia, aka low blood sugar. Dangerously low blood sugar causes weakness, vomiting, uncoordinated walking, seizures, and comas. So keep your toothpaste to yourself.

Other cat issues can seem like minor problems, but turn out to be a sign of a major one. Like excessive shedding. Shedding is a normal part of life for cats, of course, but extra shedding can be caused by a few different things. Allergies, stress, a poor diet, and fleas can all make a cat start losing its fur.

But the issue could also be something much more serious: hyperthyroidism, a disease where the thyroid gland produces too many hormones. Basically, the cat’s metabolism runs too fast. Hyperthyroidism is a common disease among older cats, and it can have seriously dangerous side effects. Thyroid hormones affect most organs in the body, so overproduction of these hormones can cause all kinds of health problems. Hyperthyroidism can make the left ventricle of the heart grow larger and thicker, which in turn can cause heart failure.

Meanwhile, all those extra hormones can also make the cat shed. A lot. Hair and weight loss are key side effects to watch for, but others include increased appetite and thirst, hyperactivity, vomiting, diarrhea, and increased urination. There are ways to treat hyperthyroidism in cats, though. A medication called methimazole, for example, decreases production of thyroid hormones. You just have to realize that something is wrong before your cat can be treated.

Cats are going to eat weird things and behave strangely no matter what. They’re cats. So there’s no need to freak out every time your kitty gets up to no good. But, there are some things they should not be doing.

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