How often you should replace your toothbrush (and the disgusting things that happen if you don't).

How often do you change your toothbrush? According to new research, probably not enough, unfortunately.

Suzanne Fischard, DDS, told RedBook magazine you probably should be changing your toothbrush every three months. Which means you should be changing your toothbrush nearly four times a year.

And because of that small fact and your lazy persona, there are probably ten million pieces of bacteria swimming around on your toothbrush’s bristles right this second, according to The Journal of Advanced Medical and Dental Science.

Delicious!

Sadly, that’s not the only gross, disgusting, very bad thing you will hear about your toothbrush today. There are still gross, disgusting, very bad things to come.

You can get sick.

Although she acknowledges that their evidence doesn’t support this yet, there’s a solid chance there’s stuff on your toothbrush right now that could get you very sick.

“I replace mine when I’ve used it after vomiting, because, well, gross. And if my kids are sick, I replace theirs, just as a precaution. The science isn’t really there to support it quite yet,” she adds.

And, um, other gross things live on your toothbrush, too.

Because I haven’t been the bearer of enough bad news today, I’d like to generously inform you about 60 per cent of brushes stored in a shared bathroom are covered in at least a little faecal matter.

That is why you should be closing the toilet lid when you flush, but don’t be fooled into thinking a little cap over the bristles will help the cause.

“Don’t cover the head of the brush with anything because bacteria proliferates so much more in moist environments” Fischard says. You should store your toothbrush upright and in open air and far away from the toilet.

To make matters just a little bit worse, 80 per cent of the faecal matter isn’t even yours.

Moving along.

You can damage your gums.

Are you one of those people that doesn't replace their toothbrush even after the bristles are completely frayed? This one's for you. Dr. Fischard says if your bristles are frayed, you might be in trouble.

"Bristles get worn down after a few months. If your brushes are fraying, you might be brushing too hard and causing damage to your gum tissue — which can lead to recession and sensitivity."

Two words: Bad breath

Perhaps unsurprisingly, if you brush your teeth with a dirty brush, it will probably leave your mouth dirtier.

Research in the American Journal of Dentistry says the best way to make sure your toothbrush is clean enough to clean your teeth is to so it in Crest Pro-Health mouthwash for 20 minutes.

"I would avoid extra scrubbing of the bristles to try to clean them or putting your brush in the dishwasher because both could damage the brush and decrease its effectiveness," Dr. Fischard says.

So... I'll see you guys at the local supermarket in about five minutes, then.