There’s actually an important reason for it
You’ve probably woken up with some crusty yellow gunk in the corners of your eyes — commonly called “sleep,” “eye boogers,” or “eye crust.” Most of us wipe it away without thinking. But once you find out what it really is, it might make you pause for a second.
🧪 What Is the Yellow Gunk in Your Eyes?
The yellow substance is called rheum. It’s a natural secretion that forms in the eyes, nose, and mouth. In the eyes, rheum consists of a combination of:
- Mucus (produced by the conjunctiva, the membrane covering your eye)
- Tears (your eye’s natural lubricant)
- Dead skin cells
- Oil (from your meibomian glands)
- Dust and debris from the environment
- Bacteria or allergens your body is trying to clear out
During the day, blinking helps spread tears across your eyes and flushes out these materials through the tear ducts. But when you sleep — you don’t blink, so the buildup collects in the corners of your eyes and dries out. By morning, it becomes that crusty or sticky yellow gunk.
😬 Why Are People “Disturbed” by It?
People are often surprised — or mildly grossed out — when they learn that this yellow stuff is:
- A mix of dead cells and bodily waste
- Potentially carrying bacteria or environmental pollutants
- Proof that your eyes are self-cleaning organs even while you sleep
While it’s perfectly normal, realizing it’s basically eye garbage collecting overnight can make people uneasy.
✅ When It’s Normal vs. When to Worry
Normal Eye Discharge:
- Small amount of crust in the morning
- Yellowish or white in color
- No other symptoms like pain, redness, or vision issues
Abnormal or Concerning Discharge:
- Green or thick yellow pus-like fluid
- Persistent throughout the day
- Accompanied by redness, irritation, itching, swelling, or blurred vision
These could signal conjunctivitis (pink eye), eye infections, blocked tear ducts, or allergic reactions — and may require medical treatment.
👁️🗨️ What You Can Do About It
- Wash your face and eyes gently each morning with clean water
- Avoid rubbing your eyes with dirty hands
- Use a warm compress if the gunk feels excessive or sticky
- If the discharge increases or becomes painful, see an eye doctor
That little crust in the corner of your eye is actually a tiny nighttime cleaning project your body completes while you rest. It’s a sign your eyes are working hard to protect and refresh themselves — even if the end result is a little gross.