Do your eyeballs grow as you get older?

If you're leaning in close to read this, then you know that vision tends to get worse as we get older. But have you ever wondered if our eyeballs grow as we age? Is our eyeball growth the reason we need to sit closer to the TV the older we get, or do our eyeballs stay the same size and are completely unrelated to our failing vision? Let's talk about how and when your eyeballs actually grow.

The science of eyeball growth 

Have you ever wondered why babies look extra, super cute? It's partly because their eyes are proportionally larger than their heads compared to adults' eyes. Your eyes grow during the first two years and then again in puberty. As you get older, your eye-to-head proportion changes up until around 20 or 21 years old.

Ocular development in infancy 

Scientists claim that babies are born with eyes that are around 16.5 millimeters in length, with "length" meaning how far the eyes go back into the head. This is around two-thirds the size of adult eyes, and with their teeny-tiny heads, their comparatively huge eyeballs are part of what makes them so adorable.

As a baby's head grows bigger in the first two years of life, it makes more room for their eyes so they can grow longer and further back in their heads, which improves their eyesight.

Puberty and adolescence 

Besides being moody and listening to music that drives their parents crazy, pubescent teens are busy growing their eyes to an adult size, which is around 24 millimeters in length. 

Adult eye development 

While eyes can and do change in adulthood, it's not because they're growing. You're all done with that eye-growing stuff by 21, so any changes to your vision after that are due to other factors, such as an increase in eye shape or weight. Yeah, you didn't know your eyes could gain weight, too? Unfortunately, scientists can't figure out a way to get them to go to the gym either.

Stability in adulthood 

Once your eyes hit that adult size of around 24 millimeters, they're done growing and stay pretty much the same length. This is partly because, around this age, your head also stops getting bigger (at least, just physically for some, right?).

Changes in eye shape 

The three main ways eyes can change in adulthood are:

• Lens size: While your eyeballs stop growing, your lens can gain weight by as much as 1.38 milligrams per year, which is what makes your grandma so squinty.
• Astigmatism: This is when there's an imperfection in how the lens or cornea curves, leading to refractive errors.
• Presbyopia: While this age-related farsightedness isn't about changes in eye shape per se, it still affects vision in adults over 40 because the lens loses the flexibility needed to properly focus. 

Factors influencing eyeball size 

While we all know that a delicious slice of pie can suddenly make your eyes bigger than your stomach, there are actually two main factors that affect eyeball size: genetics and environment.

Genetics 

For the most part, human eyeballs have developed to a particular size to maximize visual acuity, which is a fancy way of saying "to see good." However, your genes and family history can determine the actual shape and any resulting vision issues.

Environmental factors 

As with all things, a proper diet can promote healthy eye development and ongoing optimal eye health.

Debunking myths 

Judging from how many people ask if eyes keep growing as you get older, it seems to be a common belief.

Common misconceptions 

Many people mistakenly believe vision gets worse as we age because the eyeball keeps growing, kind of like how our ears and nose can keep growing as we progress in years. They are partly right, but only the lens keeps growing in weight while the eyeball itself stays the same size.

The impact of vision correction 

When you look at your grandma with her huge, thick glasses, it certainly can look like her eyeballs are bigger, but don't worry, they really aren't. It's just her glasses magnifying her eyes.

Track your eye health with regular eye exams

So, do your eyeballs grow as you get older? Nope, but your lens gains weight, and your eyeball shape can change, which can affect your vision. You can keep up with how your eyeball is changing by having annual eye exams. If you find out you need vision correction during your exam, you can order contacts online with our discounts and Gajillion Percent Promise. 

FAQs

Can certain activities, like reading or screen time, affect eyeball size? 

While these activities can cause eye strain and dryness, it doesn't affect their size. You can give your eyes a break to reduce strain by focusing about 20 feet away every 20 minutes or so.

Is it normal for eyes to feel different as you age? 

Due to changes in lens weight and eyeball shape, it's normal for people to experience issues with their eyes and vision as they age.

How often should adults have their eyes checked for changes in size or shape? 

Experts recommend having your eyes checked once a year during regular eye exams.