Introduction
Every so often I get asked about what supplements I take and why. To be clear, diet is everything and the more nutrients you can get from food the better off you'll be. I'm no expert and have no formal training, so take everything I say with a grain of salt (not medical advice: take salt at your own risk). But here's what seems to work well for me right now.
Creatine + ATP
If I could only take one supplement, it might be this. Sure creatine is found in meat, but you'd have to eat inhuman amounts to get the benefits of a small scoop or a few capsules. The particular supplement I take has added ATP, which I honestly don't understand beyond that it helps in energy production. Creatine is good for mind and body.
MSM
I was told take MSM after an injury, but it seems to help with daily recovery and seasonal allergies.
Vitamin D
I live in Michigan. No way I'm getting enough from the sun. So a supplement it is.
Fish Oil
Once again, a big concern is recovery. Fish oil is good for the heart and joints.
Essential Amino Acids
While creatine has been carefully researched and vetted, EAAs are pretty controversial. I've seen definitive arguments that they're a waste of money, and yet some of my most trusted experts use them regularly. So all that tells me is that there's more research to be done. For myself, I know that when I'm drinking this I feel better and I don't think it's all in my head.
Greens Powder
Right now there's no shortage of fresh fruits availalbe. But this winter I'll start using a greens supplement. Once again, there are plenty of arguments for and against something like this. Micronutrients are important, and a simple supplement is a convienient way for me to keep them in my diet all year long.
Conclusion
These are the things I rely on to keep me going (along with caffeine, of course). All the links give me a little kickback, so if you use them it helps me out. You should do your own research and experiment to see what works for you.