If you have a dog, you know how much they love peanut butter.

It seems like they can’t get enough of the stuff! Peanut butter is the perfect food to fill a bone with to keep your furry friend entertained during the day while you’re at work or to keep them from jumping all over your guests.

Your dog might not ever stop loving peanut butter, but some companies are using a new ingredient that could be deadly. Here’s what you need to know to keep your pup safe.

Some peanut butter companies are now using a sugar substitute called xylitol.

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Xylitol is about 100 times more toxic for dogs than chocolate.