If you spend enough time on social media, it soon becomes obvious that some people are very easily angered by very strange things. And, so far in 2018, the hot topic for people to be irrationally ticked off about is women having armpit hair.

You know, that hair that naturally grows in your armpits? The hair that everyone - regardless of gender - starts sprouting during that awkward teenage part of life? Yeah, some folks are seriously mad about it.

So, when Bella Thorne rocked the natural look while on holiday in Hawaii last week, some fans just couldn't keep their mouths shut about what was going on with her underarms.

Dressed in a red Filthy Fang bikini (her own fashion line), the 20-year-old looked happy and laid-back as she posed for a picture while leaning against a rock with her arms above her head. In doing so, she exposed her armpit hair.

Now, if this was a guy doing this, the internet would probably have nothing to say on the matter. However, as Thorne is a woman, she's apparently expected to follow some unwritten rule that every part of her body must be smooth and hairless at all times.

And so, a wave of hate poured in:

"Someone needs to hold her down and shave her frigging armpits. Absolutely disgusting," wrote Instagram user, @bmarley0420.

However, supporters of the armpit hair movement (which should maybe just be called the "being happy with your natural body and not caring about what internet trolls say movement") weren't just going to let these sorts of comments go without a rebuttal.

"Its more than okay to walk around with hairy armpits-it's natural, body hair is natural," said one Twitter user. "Go on somewhere with your 'every woman must be shaved to perfection' closeminded, mentality."

"If we took pictures of every male celebrity who went out with armpit hair, the internet would consist entirely of man pit pictures. Leave women alone. We’ll be hairy if we want to be goddamn hairy," wrote another.

And others commented to let the actress know how much she'd inspired them to be happy with their bodies: "I just want you to know how much your confidence rubs up on me," wrote one Insta user. "Be who you are, and that’s how I feel you are which made me learn to love me for who I am."

Of course, Thorne isn't the first woman to get hate for having body hair. At the end of last year, Gigi Hadid was put on blast for showing her natural pits during a campaign with LOVE Magazine; but, once again, people came to her defence:

"For all of you women commenting rude words and hating on this: You are missing the main point of this campaign.

"While you’re thinking ‘shame on Gigi for not shaving her armpits and letting me see them on Instagram (omg I won’t sleep tonite)’ you should really feel ashamed of yourself for showing us yet again that unity and unconditional love and support between each other is far from happening until there are these social boundaries that really exist nowhere but in your minds."

Thorne might be getting a lot of hate at the moment, but at least she knows that she's got millions of people on her side to back her up. There's literally nothing gross or wrong about armpit hair, and the sooner we realise that, the sooner we can stop body-shaming people for, well, having bodies.

If you spend enough time on social media, it soon becomes obvious that some people are very easily angered by very strange things. And, so far in 2018, the hot topic for people to be irrationally ticked off about is women having armpit hair.

You know, that hair that naturally grows in your armpits? The hair that everyone - regardless of gender - starts sprouting during that awkward teenage part of life? Yeah, some folks are seriously mad about it.

So, when Bella Thorne rocked the natural look while on holiday in Hawaii last week, some fans just couldn't keep their mouths shut about what was going on with her underarms.

Dressed in a red Filthy Fang bikini (her own fashion line), the 20-year-old looked happy and laid-back as she posed for a picture while leaning against a rock with her arms above her head. In doing so, she exposed her armpit hair.

Now, if this was a guy doing this, the internet would probably have nothing to say on the matter. However, as Thorne is a woman, she's apparently expected to follow some unwritten rule that every part of her body must be smooth and hairless at all times.

And so, a wave of hate poured in:

"Someone needs to hold her down and shave her frigging armpits. Absolutely disgusting," wrote Instagram user, @bmarley0420.

However, supporters of the armpit hair movement (which should maybe just be called the "being happy with your natural body and not caring about what internet trolls say movement") weren't just going to let these sorts of comments go without a rebuttal.

"Its more than okay to walk around with hairy armpits-it's natural, body hair is natural," said one Twitter user. "Go on somewhere with your 'every woman must be shaved to perfection' closeminded, mentality."

"If we took pictures of every male celebrity who went out with armpit hair, the internet would consist entirely of man pit pictures. Leave women alone. We’ll be hairy if we want to be goddamn hairy," wrote another.

And others commented to let the actress know how much she'd inspired them to be happy with their bodies: "I just want you to know how much your confidence rubs up on me," wrote one Insta user. "Be who you are, and that’s how I feel you are which made me learn to love me for who I am."

Of course, Thorne isn't the first woman to get hate for having body hair. At the end of last year, Gigi Hadid was put on blast for showing her natural pits during a campaign with LOVE Magazine; but, once again, people came to her defence:

"For all of you women commenting rude words and hating on this: You are missing the main point of this campaign.

"While you’re thinking ‘shame on Gigi for not shaving her armpits and letting me see them on Instagram (omg I won’t sleep tonite)’ you should really feel ashamed of yourself for showing us yet again that unity and unconditional love and support between each other is far from happening until there are these social boundaries that really exist nowhere but in your minds."

Thorne might be getting a lot of hate at the moment, but at least she knows that she's got millions of people on her side to back her up. There's literally nothing gross or wrong about armpit hair, and the sooner we realise that, the sooner we can stop body-shaming people for, well, having bodies.