The Vitamin Deficiency behind TIRED and STRAINED EYES

Between TVs, computers, tablets and smartphones, screen exposure is at an all-time high, and that takes a toll on your eyes. To avoid tired eyes, take both mini and longer breaks from your computers and digital devices to allow your eyes to rest.

For mini breaks, we recommend the 20-20-20 rule: Every 20 minutes, look away from your screen and focus on an object 20 feet away for 20 seconds. This gives the tiny muscles in your eye the chance to relax for a moment.
For longer breaks, we recommend you get up and stretch your legs, neck and back. While you do this, try closing your eyes to give them a bit of rest.
https://www.allaboutvision.com/conditions/ways-relieve-tired-eyes/