I'll be honest, d-ribose isn't a supplement I'm looking forward to. It's inconvenient, because I have to lug around a bucket of powder, or prepare a bottle of water pre-mixed every day. I'd love for it to be a flop lol. I just tried a scoop of 5g, and within 20 minutes, I'm finding myself jittery and uncomfortable, and really lacking in any sort of focused energy. Kind of like I get from caffeine these days. Can anyone relate? Does it change with extended use? I'd just assume less is better, but the level of benefit is so lacking, I don't know if it'd even be worth taking at a lower dose.