I suffered from some type of chronic fatigue for a few years. It was really bad. about a year ago I started sitting out in the sunlight for about 5-10 minutes every day or two. It really, really, really helped. I started to think back on when my fatigue began, and I realized that I never got sufficient sunlight whatsoever during that period. I always wore long sleeves because I was skinny. I slept during the day for a few years as well. But getting early morning or late evening sun ( to prevent harmful UV rays, it is best to avoid mid-day sun) It's really helped. So, if you aren't getting sunlight, please try it. I want you all to feel better. Eating right, being happy, getting sun... It's a recipe for energy. Don't get sunburn of course. I like to rotate my body so I can get more sunlight without getting too much sun on one particular side. I'm just trying to help. Feel free to bump this message up because I won't be returning to this forum. I noticed the sunlight helped after a couple of days. Direct sunlight is best. I like to cover my face from the sun. I like to get it on my arms and legs. It really helped and I wish I could go back in time so that I could get those years of my life back that I lost to feeling really weak.
I thought that only plants needed sunlight, but I found out ( first hand and through research that humans need it too.) I had heard stories of people who are allergic to the sun, so I figured if they aren't weak, why do I need sun? But maybe some of us need it more than others.
Please try this for your own benefit. Getting 10 minutes of morning or late evening sun is good for you ( morning is supposed to be safer, but late evening is safe enough too.)
Best of luck