If you’ve ever cut into a watermelon and it’s foamed or bubbled, it “could be dangerous”, and it’s best that you chuck it in the bin rather than eating it.

TikTok user @idksterling warned: “If this happens to your watermelon, throw it away immediately."

The influencer, who boasts 6.3million followers: added: “Many people seem to be confused as to what’s causing this”. He said he’d been tagged in a TikTok showing the foaming, and asked to explain what exactly is going on.

The social media star said it might “be your first time seeing a foaming watermelon”, saying that they are not “that uncommon”.

The TikToker also said that sometimes, the foam can be “much more pronounced” on the than in the original video he was referring to, and can be more white and “frothy”.

So what causes it, and why does the tasty treat need to be thrown away if you spot it?

“This is the result of leaving a watermelon in a place that is too hot and not ideal to preserve it”, he shared. “This is essentially the result of gas and pressure building up in the watermelon and then eventually foam being released.

“If you were to cut into the original watermelon, this is what the inside would look like”, he admitted - and it didn’t look too tasty.

The influencer said it’s “not the best idea” to eat the watermelon when it’s like this as the “fruit is rotting”, and therefore is a “prime breeding ground for certain types of bacteria”.

These bacteria can “give you food poisoning”, he said, so it's best to put it in your food waste bin to “immediately dispose of it”.

In the comments, someone admitted: "I ate that once." While another confessed: "I’ve been eating them like that."

Others said that the watermelon would be likely to have a "foul odour" if it was foaming like that too, giving more reason to throw it away.

One woman said: "I got food poisoning from eating a bad one that my mom had cut up."