Just wanted to share my experience with eye strain and what has seemed to help me. I began to develop eye issues from using a computer sometime around 2016. At first, it was just dry eyes, and I started using eye drops while at work, but after about a year, I started to get headaches too. It seemed to be triggered by computer monitors, TVs, and fluorescent lights. I went to an eye doctor twice (about a year apart) but all they did was do a standard checkup, and tell me that nothing was wrong with my eyes. I started using flux on all my screens, and avoiding caffeine and alcohol. This made it more tolerable but it was still a big problem for me.
For unrelated reasons, I decided to try to lose weight about a year ago. I looking into different methods for weight loss and discovered that a lot of people had success with what they called "intermittent fasting", which just means restricting your eating times to certain times in the day, or in my case to certain times in a 48-hour cycle. After watching a BBC documentary called "Eat, Fast, and Live Longer", I decided to try "alternate day fasting". This means that every other day, you eat only 500 calories for the day ("fasting days" even thought it's not a total fast), and then on your non-fasting days, you eat regularly.
So I tried alternate day fasting and the first few fasting days were terrible, but eventually I got used to it and kept it up for several months. I started to notice other changes in addition to losing weight. My skin cleared up and my headaches were becoming less severe. I didn't really even think of this as being a result of fasting at first, but after after hearing other people talk about similar side effects, and after watching another documentary called "The Science of Fasting", I started to think it was probably due to fasting. This second documentary talks about how fasting was researched in the USSR and found to be effective at treating things that are related to inflammation, like arthritis. I don't really know exactly what caused my headaches, but it seems to make sense that something in my eyes was being irritated and inflamed.
Anyway, I've mostly been free from the eye issues for the past several months. I still keep flux on my screens and try to limit my screen time, but it's no longer something that I think about constantly. Just wanted to share this experience in case it's helpful to others. For all I know, my issue was different than some others here, so I certainly wouldn't expect it to be a cure all. I also don't know if fasting is an appropriate suggestion for someone who isn't already overweight. I'm still not down to a weight where people suggest not doing fasting (which is normally a BMI of 20), but it might be worth a shot for some if you have a few pounds to spare. I guess it's hard to suggest something that sounds pseudoscientific like fasting without sounding like someone who tells you to use essential oils to cure cancer, but it really did seem to help me.