How to prevent (further) myopia

Myopia is the same as nearsightedness, you cannot see well into the distance and you need glasses with minus powered lenses. The number of children with myopia has grown faster in recent years. An increase has already been visible since the 1950s, but since the 1990s the number of children with myopia has grown even faster. 

On the one hand, this is due to more screen use among children, which means that they more often look closely for extended periods, and on the other hand, because children play outside less. 

How does myopia develop?

Whether your child develops myopia can be hereditary: you are more likely to develop myopia if it runs in your family. But your child's behavior can also promote the development of myopia. Especially these two behaviors: 

Looking close a lot
When you look at something, your eyes has to accommodate. This means that the muscles surrounding the lens of your eye will tighten or relax. This makes your eye lens more round or less round, which changes the strength of your eye lens. When the muscles relax, the lens of the eye becomes flatter and you can see clearly at a distance. When the muscles tense, the lens becomes more round and you can see well up close.

When you look at something close to your eye for a long time, the muscles have to be tense all the time to make the lens more round. In order to be less tense, the eyeball grows a little longer. So the muscles in your lens don't have to work as hard to get a sharp image. Unfortunately, this makes you see less clearly from afar! In myopia, your eye has grown longer. The higher your minus power, the longer your eye has grown. In order to be able to see clearly, you must wear glasses with a minus power.

Not being outside enough
Besides less looking close (compared to indoors), dopamine is produced in the lens of the eye by outside light, which prevents the eyeball from growing in length.

Is myopia bad for your child's health?

A low minus power for a child is not a problem, but if the eyeball becomes longer than 26 millimeters (normal: 23 mm) this can cause problems later in life. Research shows that a high minus power (-6 and higher) in childhood increases the risk of developing severe visual impairment later in life. This is usually caused by myopic macular degeneration, but the risk of retinal detachment and glaucoma is also increased with strong myopia. So time for action!

2 key tips to prevent (further) myopia

Apply the 20-20-2 rule for your child:

• After 20 minutes of looking close (for example on your phone or tablet) let your child look 20 seconds far away. This ensures that the eye muscles relax again after they have been tense for a while to look closely.
• Let your child be outside for at least 2 hours every day, including breaks and, for example, walking or cycling to and from school.

Of course, myopia can never be fully prevented (especially when there is a hereditary component), but these tips can help you to prevent severe myopia (which can lead to visual impairment later in life).