Nail biting is a habit that many people go through when they're younger, but manage to kick as they're likely pestered by family and friends about how gross it is. From nail varnish that tastes disgusting, to taking a sip of water every time you get the urge to bite your nails, there are many ways that you can try and give up the habit.

But most people won't realise just how disgusting the habit actually is, not realising what horrendous bacteria lurks under the nails. A viral video has made people potentially think twice before they put their fingers in their mouths

Posted by @discover_facts12 the video was captioned: "This is why you shouldn't bite your fingernails", and they urged people to "share" the video with those who do. The grim video shows someone taking a clipping from a fingernail, and dirt from under it too, and when put under the microscope, many gross things can be seen - including worm-like bacteria.

In the comments, someone joked that biting their nails had "boosted" their immune system, and someone even said: "I'm watching this video biting my nails." Another added: "As a nailbiter myself, I don't usually let s**t like this build up because I'm normal and wash my hands. Not justifying nailbiting, but [...] wash your hands and avoid this problem." Another nail-biter jokily added: "That's why I bite my nails, so that I don't have room for dirt to collect like that." Someone wrote: "I'm so glad I'm not a nail biter."

One doctor has shared that by biting your nails, however, you could be putting your sight at risk. Dr. Saya Nagori is an expert ophthalmologist and the founder of Eye Facts, an educational platform dedicated to eye health and vision preservation, and she told the Daily Star: "That unsettling video reveals what lurks beneath our nails isn't just keratin, but a mix of uninvited microbes too. Staphylococcus, Streptococcus, and E. coli - not ideal party guests."

She acknowledged that biting your nails may temporarily ease stress, but warned that there may be "consequences" if you do it. She said that if you bite, "microbes" are put into your mouth, which can potentially cause "infections." And if you wear contact lenses, having such dirty nails is also a risk as "it risks transferring germs directly to the eyes."

Dr Nagori also warned that there's a "fine line between beneficial and detrimental" that we should walk "cautiously." She said: "In my work, I've seen nail-biting transfer bacteria from fingers to eyes, causing anything from mild irritation to severe infection. How habits manifest in our unique bodies is complex."

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