Dark mode can reduce eye strain in low-light conditions. 100% contrast (white on a black background) can be harder to read and cause more eye strain. It can be harder to read long chunks of text with a light-on-dark theme.
It makes intuitive sense: brighter lights seem to be a little rougher on the eyes, and white is a higher-energy color, so it probably uses more battery, right? As usual, though, reality is a little more complicated.
Protect eyes, sleep with dark and night modes
And as far as your vision goes, how much your experience will improve with a dark theme depends heavily on your eyes and the ambient light situation where your screen is. Also read: Do dark themes save energy? This is relatively straightforward: does your device use? If it does, then dark themes can save you power! True black hex 000000 is the only color that will turn off the pixel, though.
Switch Your Devices to Dark Mode to Give Your Eyes a Break
Any other color will draw more power, with white being the most expensive to display in terms of electricity consumption. The science is pretty clear here, which is nice. Also read: Do dark themes help your eyes?
This is where things get a little trickier: because dark themes are better for your eyes sometimes, but not all the time.
In terms of readability, the verdict is clear: black text on a white background is the best. This comes down to the properties of color, light, and the human iris. This is especially true for the 50% of the population that has astigmatism. All this actually does have an effect: scientific studies have found repeated evidence that text readability is significantly improved by dark-on-light vs.

Starting at a white screen for a long time certainly feels worse, but the scientific jury is still out, and the colors may not really be the problem. What does this actually mean? If you do a lot of reading on your screen, you should probably stick to a dark-on-light theme maybe a light gray background with black text and try to control your screen brightness and your ambient light situation instead of changing the colors. I like the dark side!

If you like using dark themes, go for it! Whatever makes your eyes happy or satisfies your aesthetic fancy.
