Have you ever wondered why some kids need glasses to see clearly? It all has to do with the shape of our eyes. To see things sharply, our eyes need to be just the right shape. But for about half of the kids around the world, their eyes grow too long, making their vision blurry.
When babies are born, their eyes are usually short. As they grow, their eyes get longer, and the lens and retina inside the eye move farther apart. By the time a child is around 6 years old, their eyes are usually the perfect length to focus light correctly and create a clear picture on the retina. At this point, the brain tells the eyes to stop growing.
However, in recent decades, many kids—more than 90% in some countries—have eyes that keep growing longer than they should. This makes light focus in front of the retina instead of right on it, causing a blurry image.
For a long time, scientists thought screens were to blame because kids were spending a lot of time looking at things up close. Our eyes are best at focusing on things that are a little bit away from us. To see far away, our eye muscles stretch the lens, and to see up close, they squeeze it. Scientists guessed that kids’ eyes were growing longer to help them see close things better without straining, but this made it hard to see far away.
Recent research shows that spending a lot of time in front of screens doesn’t necessarily make kids’ eyes longer. Instead, it seems that a hormone that tells the eyes to stop growing might be missing. We don’t fully understand how this hormone works, but we know that eyes need enough light to make it.
Today, kids spend about half as much time outside as their parents did. This means they aren’t getting enough light for the hormone to develop and signal their eyes to stop growing. As a result, their eyes keep getting longer, leading to more blurry vision.
Luckily, there’s an easy fix for future generations: spend more time outdoors! Playing outside in the sunlight can help make sure your eyes get the light they need to grow properly and stay healthy.
Create a simple model of the human eye using clay or playdough. Shape the eye to show how it changes from birth to age 6, and then demonstrate what happens when the eye grows too long. This will help you understand how the shape of the eye affects vision.
Keep a diary for one week, recording how much time you spend outdoors each day. At the end of the week, calculate the total time spent outside and discuss how it compares to the recommended amount for healthy eye development.
Conduct an experiment to see how distance affects your ability to focus. Use a book or a small object and try to read or see it clearly from different distances. Record your observations and discuss how this relates to the eye’s ability to focus on near and far objects.
Prepare a short presentation debunking the myth that screens are the main reason kids need glasses. Use information from the article to explain the real reasons behind eye growth and the importance of outdoor time.
Design a weekly outdoor activity plan for you and your friends or family. Include a variety of activities that can be done in natural light, such as hiking, playing sports, or having a picnic, to ensure you get enough sunlight for healthy eye development.
To see things clearly, your eyes need to be a certain shape. However, around half of the world’s children have eyes that are too long, resulting in blurry vision.
Welcome to MinuteEarth. Most babies are born with short eyes, but as they grow, their eyes lengthen, and the lens and retina move farther apart. By the time a child is about 6, their eyes are typically the right length for the lens to focus incoming light and form a clear image on the retina. At that point, the brain signals the eyes to stop growing.
However, starting a few decades ago, many children—over 90% in some countries—continued to have their eyes lengthen beyond the ideal point. This causes light to focus in front of the retina instead of directly on it, resulting in a fuzzy image.
For years, scientists believed this was due to screens, as children were spending most of their time looking at things close up. Our eyes focus best on objects at a middle distance. To see far away, the eye muscles must stretch the lens, while to see close up, they must compress it. Scientists speculated that children’s eyes were growing longer to allow them to see close objects clearly without straining, but this left them unable to focus on distant objects.
Recent findings suggest that children who spend a lot of time in front of screens do not necessarily have longer eyes than those who don’t. Instead, it appears that a hormone responsible for signaling the eyes to stop growing may be lacking. We still don’t fully understand how this signaling process works, but we know that eyes need exposure to a certain level of light for the hormone to form.
Today’s children spend about half as much time outside as their parents did, meaning they aren’t getting enough light for the hormone to develop and signal their eyes to stop growing. Consequently, their eyes continue to lengthen, leading to an epidemic of blurry vision.
Fortunately, there’s a simple solution for future generations: spend more time outdoors!
Eyes – Organs in our body that allow us to see the world around us. – Our eyes help us read books and see the colors of a rainbow.
Vision – The ability to see things with our eyes. – Good vision is important for playing sports and watching movies.
Light – A form of energy that allows us to see when it enters our eyes. – Plants need light to grow, just like we need light to see.
Hormone – A chemical in our body that helps control how we grow and feel. – The hormone melatonin helps us feel sleepy at night.
Outdoor – Relating to being outside in the open air. – Playing outdoor games is a fun way to stay active and healthy.
Health – The state of being free from illness and feeling well. – Eating fruits and vegetables is good for our health.
Blurry – Not clear or sharp; difficult to see. – Without my glasses, everything looks blurry to me.
Shape – The form or outline of an object. – The shape of a leaf can help us identify what type of tree it comes from.
Kids – Young children or young people. – Kids need plenty of sleep to stay healthy and grow strong.
Retina – The part of the eye that receives light and sends signals to the brain to help us see. – The retina is like a camera that captures images for our brain to understand.
