What discussion of missing vitamins would be complete without mentioning Dr. Bruce Ames? :) https://www.youtube.com/watch?v=wrfxdtXjXHs
There are many more videos by him, explaining very complicated parts of the metabolism. About 10 years or so ago, he was part of the much missed UCSD video series on Aging. Most of his videos are now either on Youtube or Vimeo. Whatever you think of his selling "Juvenon" and other supplements on the side, he is still a treasured scientist in this area. He's 88.
Thanks for the resource, I do take many of these in doses that are beyond what is recommended by websites and many do help. I've got a problem taking Biotin though. I may try again after my body re-balances with the new tyroid drug I'm on (which seems to be working wonders).
I hope you and yours are safe and healthy, but most of all, happy.