You rely on your eyesight for just about everything. But how much do you really know about your eyes? (Did you know, for example, that each eye is moved by six muscles? Or that your iris has 266 unique characteristics?)  

Whether you’re new to eyeglasses and contact lenses or have been wearing them since elementary school, there’s always more to learn about your eye health.  

Take this fun quiz to test your ocular knowledge. You may learn a few surprising facts along the way.  

True or false: Playing video games every day increases your child’s chances of needing to wear eyeglasses.  

Somewhat true 

Your child’s eyesight is mostly determined by genetics, says Brian Rashid, O.D. He’s an optometrist at Buckeye State Optometry inside America’s Best Contacts & Eyeglasses in Columbus, Ohio.  

“Hobbies and screentime play a smaller role in determining a child’s prescription,” says Dr. Rashid.   

The bigger concern, he says, is that staring at a screen can cause eyestrain — especially if that screen is held too close to your face or if the brightness is too high.  

The reason: “When you look at something up close, your eyes adjust by flexing the muscles inside the eye,” he says. And long periods of close-up focusing can tire out those small (but mighty) muscles.  

To be clear: Keeping those eye muscles flexed for too long doesn’t play a huge role in making you nearsighted, Dr. Rashid says. But it can strain your eyes. This could bring on symptoms such as soreness, fatigue, and trouble concentrating.  

One simple solution is to balance family screen time with plenty of fresh air and outdoor activities. 

Eye exams are an essential part of your health care routine. Book an appointment with your America’s Best optometrist today.  

True or false: A woman’s vision changes during pregnancy.  

True 

Hormones can be blamed for many pregnancy symptoms, including eye-related ones. But it’s more common for vision changes during pregnancy to be caused by gestational diabetes, or high blood sugar. The condition affects up to 10% of all pregnancies in America, according to the Centers for Disease Control and Prevention (CDC). 

“Gestational diabetes can change the thickness of the lens in the eye, so it changes your glasses prescription,” says Dr. Rashid.  

Once your blood sugar levels drop or your pregnancy is over, your eyesight should return to normal (or close to normal) within a few weeks, he says. 

In the meantime, you may need a new pair of eyeglasses or contact lenses until normal hormone levels are reached, he says.  

True or false: Doing eye muscle exercises can help improve your child’s vision. 

True 

To a point, that is. Eye exercises can help children who have accommodative eye disorders, says Dr. Rashid. Those are conditions in which the eyes don’t work together to focus properly.  

For example, some children have trouble focusing both of their eyes on close-up objects (called convergence insufficiency). In that case, exercises like pencil pushups — in which a person focuses on a small letter on a pencil while bringing it toward the bridge of their nose — can help train the eyes to align in sync. 

“We get patients all the time that say, ‘The school said my son or daughter is dyslexic,’” says Dr. Rashid. “But once you train their eyes to move correctly, they don’t have symptoms of dyslexia anymore. Sometimes it’s just an eye movement or accommodative problem.”  

If your child has an accommodative eye problem, your optometrist can either treat or refer you to a vision therapy clinic. There, an optometrist who specializes in vision therapy can teach your child how to perform these exercises.  

Keep in mind that the exercises tend to work best when children are between the ages of 5 and 12, Dr. Rashid says. Once they’re a teenager, it becomes harder to retrain their brain to see objects differently.  

One thing these exercises can’t correct? Refractive errors. That means the eye is unable to bend and focus light properly, so vision may become blurry or hazy. Examples include nearsightedness and farsightedness. For that, your child will need eyeglasses, says Dr. Rashid. 

True or false: A loss of peripheral vision is just a natural part of the eye’s aging process.  

False 

Losing peripheral vision (side vision) could be a sign of a serious eye disorder, says Dr. Rashid. Examples include glaucoma, diabetic retinopathy, or retinitis pigmentosa (a genetic condition that affects the retina).  

The problem is that it can be hard to notice when your peripheral vision starts to falter. “It’s often a lot easier to notice a loss of your central vision,” adds Dr. Rashid. 

The best way to spot serious eye diseases in their early stages is by scheduling a comprehensive eye exam with an optometrist every year. Use our search tool to find a provider near you.  

True or false: Eating carrots will improve your eyesight. 

False 

Dr. Rashid’s patients often ask him if eating carrots can improve their vision. And unfortunately, the answer is no.  

“It’ll help make your eyes healthy,” he says. “But no amount of carrots is going to fix an astigmatism or make you less nearsighted or farsighted.” 

Carrots contain a pigment called beta-carotene. It functions as an antioxidant that shields your eye for excess stress.  

One example: It can help preserve the macula, an area in the back of the eye that allows for central vision. That’s one reason you can find beta-carotene in certain eye vitamins that are designed to reduce the risk of age-related macular degeneration.  

Recommended reading: 5 Best Foods for Eyes That Aren’t Carrots  

True or false: Vision loss is always irreversible. 

False 

It’s true that some eye diseases can cause permanent vision loss. For example, macular degeneration and glaucoma, Dr. Rashid says. That said, the right treatment can help preserve a person’s remaining vision or slow the progression of vision loss. 

In other cases, it’s possible for vision loss to be restored. Cataracts, for example, are the leading cause of vision loss in the United States, according to the CDC. But cataract surgery can correct the problem.  

Blurry vision caused by diabetes-related macular edema can also potentially be reversed with the right treatment, according to the American Diabetes Association. 

There are also temporary causes of vision loss, such as migraine with visual aura, Dr. Rashid says.  

Another short-term cause of vision loss is optic neuritis, which is often associated with multiple sclerosis. It happens when blood flow to the optic nerve is interrupted.  

“Your vision will be diminished in one eye, but it will most likely return,” Dr. Rashid says.  

If you have questions about your eyesight or are experiencing sudden vision loss, call your eye doctor or seek emergency treatment.