Vitamin D3
Helps regulate the amount of calcium and phosphate in the body. It's good for bones, teeth and muscles. The NHS recommends that even healthy people should consider taking a daily supplement, especially as we head into the winter months.
EPA / Omega-3 from fish oil
Good for your heart, brain, eyes, and joints. I like fish, especially oily fish, but I hate the smell and cleanup after cooking fish, so I inevitably don't eat enough to get the required amount.
L-Theanine and Ashwagandha KSM-66
I use these two in combination for better sleep and to reduce stress.
I find L-Theanine helps reduce caffeine jitters and some research has shown that Ashwagandha can improve athletic performance, including increasing VO2 Max.
Creatine
As-per my previous post.
General multi-vitamin
Just as a top-up for anything I might be missing out on through my normal diet. Although I try to eat a healthy diet, I'm probably (literally) ****ing away 99% of this one.
As to why I don't take other supplements — I've looked into quite a few others such as Magnesium Threonate and Glycenate and Beta-Alanine but I've discounted them either because of the cost (in the case of a good Magnesium supplement) or because I doubt I will benefit from the marginal gains in taking it (in the case of Beta-Alanine).
How much caffeine do you have that leads to the jitters?