“No. Crossing your eyes on purpose will not damage your eyes or cause them to become permanently crossed. You may temporarily experience eye strain, blurred vision or a headache if you hold your eyes crossed for a long time, but your eyes should return to their normal position when you relax them. A persistently crossed or turned eye is called strabismus, and it has other causes that should be assessed by an eye doctor.”
There. You can finally tell your mother she was wrong. About this one thing, anyway.
The idea that crossing your eyes will make them “get stuck” is one of those eye-care myths that seems to get passed from one generation to the next. I heard it as a kid, and I still hear parents say it today.
Fortunately, that's not how your eyes work.
Let's look at what actually happens when you cross your eyes, why you can do it in the first place, and when a crossed eye really is something you should be concerned about.
Why Can We Cross Our Eyes?
Your eyes are constantly moving together to allow you to look at objects at different distances.
Each eye is controlled by six extraocular muscles. Together, these muscles move your eyes up, down, left, right and through more complex combinations of movement. Your brain coordinates the muscles in both eyes so that they normally point toward the same object.
When you look at something close to you, your eyes naturally turn inward toward your nose. This is called convergence.
Try holding your finger at arm's length and slowly bringing it toward your nose. Your eyes will progressively turn inward as you continue looking at it.
Crossing your eyes on purpose is essentially taking that inward movement farther than you normally need to.
You're not breaking your eyes. You're asking your eye muscles to hold an unusual position for a while.
Can Crossing Your Eyes Damage Your Vision?
No. Occasionally crossing your eyes does not damage your vision.
It won't make you nearsighted. It won't make you need glasses. And despite what you may have been told as a child, your eyes aren't going to suddenly lock into that position.
Holding your eyes crossed for an extended period can, however, become uncomfortable.
You may notice temporary symptoms such as:
eye strain or tired eyes
temporary blur
difficulty focusing
a headache
occasionally double vision while you're doing it
Once you stop and allow your eyes to return to their normal position, those symptoms should resolve.
So if your eight-year-old discovers they can cross their eyes and thinks it's the funniest thing they've ever done, you don't need to panic.
They'll probably get bored before their eye muscles do.
Can Crossing your eyes make them stay like that?
No. This is a myth.
Intentionally crossing normally aligned eyes does not cause them to become permanently crossed. The muscles controlling eye movement are designed to move the eyes in many different directions, and voluntarily turning them inward does not cause strabismus.
But there is an important distinction here.
If an eye turns inward or outward when you're not doing it intentionally, that's different.
That may be strabismus.
What Is Strabismus?
Strabismus is a condition in which the two eyes are not properly aligned. One eye may turn inward, outward, upward or downward relative to the other.
An inward-turning eye is called esotropia, while an outward-turning eye is called exotropia. Strabismus is estimated to affect up to about 4% of the population.
There are many possible causes. Some forms develop during childhood and may be associated with refractive error or differences in vision between the two eyes. Other forms can occur later in life because of problems affecting the eye muscles or the nerves controlling them, vision loss, thyroid eye disease, trauma, neurologic conditions or age-related changes.
In other words:
Crossing your eyes doesn't cause strabismus. Strabismus causes an eye to cross when you aren't trying to do it.
That's the distinction I'd really want parents to remember.
Is a Crossed Eye in a Child Serious?
This is where I'd pivot the article from a fun myth-busting post into something genuinely useful.
A child intentionally crossing their eyes is usually nothing to worry about. A child whose eye crosses on its own should be examined.
When the eyes aren't properly aligned during childhood, the brain may begin favouring one eye over the other. That can interfere with normal visual development and may contribute to amblyopia, commonly called “lazy eye.”
Earlier assessment matters because children's visual systems are still developing.
If you notice that one of your child's eyes consistently or intermittently turns inward, outward, upward or downward, especially when they're tired or focusing, book an eye examination rather than assuming they'll grow out of it.
““If an adult suddenly develops a crossed or turned eye, especially with new double vision, we consider that an acquired strabismus. That’s very different from intentionally crossing your eyes. In adults, there is often an underlying condition causing the change that needs to be identified and addressed. A new eye turn or sudden double vision should always be evaluated promptly.””
So, Is Crossing Your Eyes Bad?
No. Crossing your eyes for fun will not damage your vision or cause your eyes to stay crossed permanently. You might notice some temporary eye strain, blur or a headache if you keep doing it for too long, but your eyes should return to normal once you relax them.
What matters is whether you're crossing your eyes intentionally or an eye is turning when you don't want it to. A persistent or recurring eye turn, particularly in a child, should be examined because conditions such as strabismus can affect how vision develops.
If you've noticed an eye turn in yourself or your child, talk to your optometrist. At Helio Optometry in Edmonton, we can assess vision, prescription, eye alignment and overall eye health to help determine what's going on and whether treatment or further evaluation is needed.
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