Tonight I'm participating in Swissper's #SleepNaked Twitter Party! If you were on Twitter, you saw me answer a few beauty questions sent in by my readers. I thought 140 Characters wasn't enough to really answer these questions, I decided to write more complete answers for the blog!
This is a really great question! I've often wondered it for myself, but since I'm an not an ophthalmologist, I asked one of my favorites, a med school classmate who practices in Nashville. She said that she cautions patients against using eyeliner on the inner eyelash line because of 2 main reasons: first, there is a risk of harming your cornea or conjunctiva with the pencil if you slip. A corneal abrasion will heal, but it is very painful! Second, the Meibomian Gland orifices are there, and they're important for tear film health.
What little glands is she talking about? You can see the openings in this image from Gray's Anatomy (the classic medical textbook, not the ABC show). There are about 50 of those little holes on your upper lash line, and 25 on your lower lash line. They secrete something called Meibum, which is an oily substance that helps your tears from drying up basically. You want these glands to be open and to secrete normally. If they get backed up, you'll have dry eyes. The glands can get inflamed, this is blepharitis (not fun).
How do you minimize the effect of eyeliner, if you do chose to wear it?
1. Use a softer eyeliner
My friend mentioned the risk of injuring your eye with the pencil, and that is a real concern! It stands to reason that using a very hard pencil is going to injure your eye quite a bit more than a softer pencil would if you happen to slip and hit your eye. My favorites include Elizabeth Arden, Urban Decay, Too Faced, CoverGirl, and L'Oreal.
2. Apply below the lash line, not directly to the waterline.
In the picture above, I applied my eyeliner to the lashline, and immediately below it. This is definitely better than right in my waterline as far as effects to the Meibomian Glands, but if you look closely, you'll notice that there's still liner on that waterline, it's moved.
A recent article in Eye Contact Lens (yes, it's a journal) found that eyeliner applied outside of the lashline (not on the waterline) takes longer to migrate into the eye and less of it gets into the eyes. However, even liner outside of the lash line gets into the eyes. If you have dry or sensitive eyes, this might be a good reason to avoid eye liner completely.
3. Remove your eyeliner and eye makeup completely every night
It's definitely best to fully remove your eyeliner every night. I recommend using one of my favorite eye makeup removers and a quality eye cotton round (which won't leave fibers all over your eye!). Tonight's Twitter party was sponsored by Swisspers, but I fully admit that I agreed to work with them because I will only buy their exfoliating cotton rounds. They're a bit textured, so they grab onto eyeliner and mascara a bit better.
Images: iStockPhoto and WikiMedia