I wrote a book about eye health called The Eye Diet. It kept me from needing to switch to the nightmare of trifocals. But almost no one has read it. So I decided to make a short, simple summary for a busy world. The book has all the research, but here are a few of the things I found. 
One, eye sight is not a one way downhill slide. We lose most of our eyesight during our teens, and then during our perimenopausal years (sorry guys, our hormones change too). Otherwise, sight tends to be pretty constant. 
Two, ten hours a day of screen time does permanently affect sight. We are seeing a pandemic of extreme nearsightedness that promises to enormously increase legal blindness across the globe. 
And three, the good news, there are simple things you can do to help your eyesight. 
Get outside. Use natural light to read by. Get your children outside. We do not have artificial light that can match the sun. If you are having trouble reading, practice using the sunlight.
Practice can improve your eyesight. I know, experts say it doesn’t make much difference. They are wrong (read the book). Start by doing eye push ups without your glasses in sunlight. 
What’s an eye push up? 
Look at a typewritten page (paper is preferable). Bring it slowly closer to your eyes until it becomes blurry. Then bring it farther away from your eyes until it becomes blurry. Practice holding it in focus ten times. 
Now add two more exercises: Nose Staring and Paranoid Eagle. They stretch and exercise the two muscles that wrap around your eye and can contribute to poor eyesight. 
What’s Nose Staring?
We all think of this as crossing our eyes. But you want to move both eyes down and in so that you are looking at your nose. While you do this, wonder why your eye developed a muscle to do this unless it was supposed to help with eye focus. 
What’s Paranoid Eagle? 
How many times a day do you look up at the outside edge of your eyebrows? Did you know you have a muscle for that precise motion? Either it’s supposed to help with the focus of your eyes, or there was an evolutionary reason for that muscle. Since officially your eye muscles don’t help focus your eyes (read the book) I named this motion Paranoid Eagle. The only reason you’d need this muscle is if you were looking for eagles to come swooping down on you all the time. So practice Nose Staring and Paranoid Eagle ten times a day.
Finally, a little knowledge. Your eyes only relax in absolute darkness or when gazing gently at the horizon. You know, the horizon, where the curve of the earth bends it out of your view? That horizon. How often do you look at the horizon in your daily life?
Do not throw away your glasses! Use proper lenses or no lenses at all if you don’t need them. How many of you have computer glasses? They are much weaker glasses you should be using for screen time. You can get them with polarizing coatings, etc. but the big thing is that your prescription is written for the horizon, not two feet away from your nose. A child given too strong lenses will have a worsening of eyesight within two hours. Don’t make your eyesight worse by using too strong lenses. 
For the vast majority of the world who can’t afford multiple lenses (and the millions who can’t even afford glasses), make yourself  pinhole glasses. A piece of paper with a pinhole in it will improve your eyesight greatly while lessening the stress of all that excess light on your eyes. Put the paper on a pair of frames, or just hold it up to your eye while you read. 
Want more? Read The Eye Diet.
On Amazon
At Smashwords (Also Barnes And Noble, etc.)
Or better yet, listen to me read it to you.
On Google Play or Audible
Just want the research? It’s here