What Are Double Eyelids?

Medically Reviewed by Whitney Seltman, OD on May 29, 2024
5 min read

Did you know that there are different types of eyelids? If you have double eyelids, you can probably see creases in your eyelids when your eyes are open. If, on the other hand, you have monolids, or single eyelids, your epicanthal fold — which is the skin on top of your eyelid — extends to the inside corner of your eye. 

Eye shape and size are different around the world, and so are preferences for a specific type of eyelid. For example, if you’re a person of English descent who lives in America, you may have never given a second thought to your eyelids — but in Korea, getting eyelid surgery to make one’s eyes look bigger is very common. 

Blepharoplasty, or eyelid surgery, is also performed for medical reasons. If you have drooping eyelids because of age, or if you have trouble seeing clearly because of heavier eyelids, you may wish to schedule a plastic surgery consultation to make yourself more comfortable. Learn more about blepharoplasty, when it’s necessary, and who is a good candidate for this procedure.

This term simply refers to the crease in some people’s top lids and the absence of extra tissue, which creates the appearance of two lids. Whether you have double eyelids or monolids depends on your genetics.

Double eyelids. Double eyelids have a visible crease on the top eyelid when the eyes are open and little to no epicanthal fold. These eyelids are more common in people of non-Asian descent.

Monolids. Monolids, or single eyelids, have an epicanthal fold that covers the bottom part of the eyelid and extends to the inside corner of the eye. This gives it the appearance of being a “single” lid. Monolids are most common in people of East Asian descent.

Hooded eyelids. Hooded eyelids are not monolids, but they are top-heavy and can give the appearance of a single lid. Some people develop hooded eyelids as they get older due to normal age-related eyelid drooping.

Eyelid shape and size, like hair and eye color, are mostly determined by genetics — and it might surprise you to know that, even among people with Asian ancestry, eyelid shapes can vary a lot. Additionally, babies of all ethnicities start life with heavier epicanthal folds. Some of these babies will develop double eyelids by the time they are young children, while others, usually those of East Asian descent, will keep their single eyelids throughout their lifetime. 

There are also a few genetic conditions like Down Syndrome that cause people, regardless of their ethnicity, to have more prominent epicanthal folds.

It’s commonly assumed that people of European descent typically have double eyelids while East Asian individuals have monolids — but this is an oversimplification. For example, one study on eyelid shape found that half of the Latino people in the study had monolids or epicanthal folds. Many people around the world, regardless of their ethnic background, have heavier, or “hooded,” eyelids as well.

A blepharoplasty is an eyelid procedure where the surgeon removes extra eyelid tissue and fat. Everyone’s eyelids droop a little bit as they age, but some people experience uncomfortable sagging of this tissue, which is a condition called "ptosis" that sometimes gets in the way of their vision. 

Note that monolids are not the same as ptosis: Monolids are simply another type of normal, healthy eyelids.

Sometimes, doctors perform blepharoplasties for cosmetic reasons. Elective, or non-medical blepharoplasties, can make the eyes look bigger by removing extra tissue on the top eyelid and creating the appearance of an eyelid crease.

Before the blepharoplasty, the surgeon uses a local anesthetic to numb the area or puts you under general anesthesia. During the procedure, the surgeon makes a tiny incision and then removes the extra tissue or fat from the desired location. There is a moderate recovery period after the surgery, usually lasting about a week, but some people will take longer to fully heal.

Pros. There are many great reasons to get a blepharoplasty if you need one. It’s one of the most common plastic surgery procedures for a reason: There’s minimal pain, little downtime, and it can make a huge impact on your overall looks — even though the change itself is subtle. 

Consider these pros when deciding whether to get the surgery:

  • It can “lift” your eyelid and help you see.
  • It can stop eye irritation from eyelashes that are getting pushed into your cornea by heavy lids.
  • It can make you look more youthful and make your eyes appear bigger.
  • It can help you more easily apply eye makeup such as eyeshadow and eyeliner.

Cons. Blepharoplasties are generally safe outpatient procedures as most of the physical side effects are short-lived. Consider the following cons of this procedure, though:

  • It can cause uncomfortable itching, swelling, bruising and double vision immediately after the surgery, and sometimes these side effects persist. It can sometimes lead to dry eyes if the surgery causes the lids to not be able to close all the way. 
  • If the surgery was cosmetic, it may actually make you feel uncomfortable about the new way you look.
  • According to the American Academy of Ophthalmology, blepharoplasty is the most asked-for surgery in Asia. If you feel pressured into getting cosmetic surgery by your family, friends, or culture, you may end up regretting your choice.

You can’t reverse a blepharoplasty, and double eyelid surgery is often quite expensive. This means that if you do want to surgically alter your eyelids for cosmetic reasons, you need to be absolutely sure that this is what you want. You should wait until you’re old enough to decide for yourself.

Blepharoplasty can sometimes be very helpful in alleviating eyelid problems that cause vision problems — but it’s crucial to remember that both double eyelids and monolids are normal, healthy eyelids. If you wish to consider surgery for yourself for cosmetic purposes, make sure to speak to your doctor and perhaps a trusted friend or mental health counselor to make sure you’re undergoing this procedure for the right reasons.