"Have a look at the second pic... That's what that s*** does to your tongue, imagine what's it like on your internals?
"Up until recently when this started to occur I was drinking at least 5-6 a day (lack of energy teaching kids usually) and I brush daily, went to the doctor and boom! Found out it's the chemicals in these drinks that are causing it... It literally eats away at your tongue.
"So be wary guys."
Royals also confessed to smoking cigarettes, but believes the damage is purely due to his energy drink consumption.
He also wrote: "Just to make it clear, I actually do care for my oral health but this is purely from these drinks... I do smoke but has nothing to do with the eating away of my tongue," he said.
While Royals didn't go into specific details about how this could occur, a study by World Health Organisation researchers quotes findings from the US: "A study in the US showed that dental cavities can result from the acidic pH and high-sugar content of products such as energy drinks.
"Another study showed that consumption of energy drinks can cause erosion and smear layer removal in the teeth, leading to cervical dentin hypersensitivity."