What is eye sleep and what causes it?
Why does eye sleep form?
When you wake up in the morning, you probably have found some eye sleep, sand or gunk in the corners of your eyes. It goes by a few different names, but the official term for eye sleep is ‘rheum’. It’s totally normal – in fact, it’s just a combination of eye debris and tear film which hardens overnight. When you sleep, this falls into your eye’s inner corner and dries up, which is what forms the familiar crust. During your waking hours, you blink around 20 times a minute which removes excess eye discharge, washing away any debris and bacteria. Blinking also coats your eye in tear film, keeping it hydrated. However when you sleep and therefore aren’t blinking, any eye discharge remains in your eye, collecting throughout the night. In additional to this, you actually produce more eye discharge overnight as, when you sleep, your meibomian gland ducts are relaxed, thereby releasing more of your tear film’s oily substance. Cooler temperatures at night also cause your eye discharge to harden, forming the crust.
What other causes of eye sleep are there?
Although eye sleep is very normal and almost everyone will experience it, there are certain conditions and diseases which may affect the amount of eye sleep you develop overnight. If you notice any significant changes to your eye sleep, it could be caused by one of the following conditions:
- Conjunctivitis (viral, bacterial, allergic)
- Eye infections
- Blepharitis
- Meibomian gland dysfunction
- Stye
- Dry eyes
- Contact lens intolerance
- Corneal ulcers
If any significant change to your eye sleep is accompanied by eye pain, light sensitivity or blurry vision, you should visit your optician as soon as possible. Your eye sleep also shouldn’t be bright yellow or green in colour and this again indicates that you should have your eyes checked.
Why does eye sleep sometimes look different?
Aside from any of the conditions we mentioned above, your eye sleep might change in colour and consistency on a daily basis anyway. This depends on how much of it evaporates throughout the night, and on the make-up of your tear film. The tear film in your eyes has three components: one oily, one watery, and one mucus-like. Each of these elements of the tear film comes from a different gland in different parts of the eye. The oily part is produced by glands in the eyelids, the watery component comes from glands above the upper eyelid, and the mucus part is produced by cells in the white of your eye.
The balance of these three components needs to be correct in order for your eyes to be well-hydrated, not tearing up excessively, and able to wash away any debris effectively. If the balance of your tear film is off, you may find that you have more eye sleep than usual, or that it changes colour and consistency. A number of factors can influence your tear film make-up, such as diet, hydration and exposure to digital screens. Read more about this on our blog.
How can you remove eye sleep?
You should never try to pick or scratch your eye sleep away. Doing so increases your risk of injuring the delicate skin around your eye, or even scratching your cornea. Instead, you should hold a warm flannel against your eye to soften the sleep and then gently wipe it away. Picking out your eye sleep can also occasionally result in you accidentally pulling out your own eyelashes, only causing further irritation.
Before you touch your eyes, it’s important to wash your hands to prevent infection from occurring – which would only be counterproductive given that eye sleep is a way of collecting debris and removing it from your eyes!
How can you avoid an eye infection?
Given that eye sleep occurs more when your eyes are fighting off an infection, it’s important to know how to prevent eye infections to keep your vision safe. Our top tips for keeping your eyes free from infection and bacteria are:
- Not touching your eyes without reason
- Washing your hands regularly
- Disposing of infected makeup
One of the main causes of eye infections and eye irritation is actually contact lenses, particularly daily disposable contact lenses. This is because bacteria on your fingers can easily transfer onto the contact lens and then onto your eye. You’re actually 10 times more likely to experience vision loss from contact lens complications than you are from eye surgery ‘going wrong’, and you can read more about contact lens infections and intolerance on our blog. Perhaps looking into laser eye surgery is your next option if you find yourself struggling with eye infections and discomfort due to contact lenses.
Read more about laser eye surgery on our website, and discover if you’re suitable for treatment by visiting us for a free consultation. Book online or call us on 0800 093 1110 to start your Optimax journey.
