You have highlighted specific segments of the population, which actually supports my argument. As I had stated, the blanket statement that everyone reading this forum should get on the vitamin sticky regimen is, in my opinion, something that should not be done. Many may not be informed that there are possible negative outcomes associated with long-term vitamin supplementation. In my personal opinion the recommendation to get on the vitamin sticky regimen is misguided and inappropriate. Every concussion is different and individuals may or may not need such supplementation

Recommending someone have blood testing for potential vitamin deficiencies and subsequently developing a vitamin regimen based on the results is completely different. This is both appropriate and possibly relevant for people recovering from an mTBI, and would be done under the care of a physician rather than through and e-based forum suggestion. I think the moderators should carefully consider restricting such endorsements, and I have to admit I'm surprised that this is not only permitted but appealingly endorsed.

On the note of a healthy diet, I do not think this is difficult to achieve if one chooses to do so. We have a globally-enabled food supply with a wealth of choices available usually year-round (e.g. season-based produce are no longer seasonal). However, for a minority of the population they may be faced with challenges (lactose intolerance, vegan, use of proton antagonists, etc) in which other choices are needed. If the diet is unable to meet nutrient needs, then of course supplements are a viable option.

As for the supportive literature, if I feel I'm up to it I'll see if I saved the articles or whether I need to find them again. As an aside, I worked closely with high-level human nutrition researchers who specifically study supplementation and not one of them recommends a daily vitamin. Even supplementation of our staples (milk, bread, grains, etc.) is being evaluated in at risk populations, particularly pregnant women. I suspect the next decade of macro and micro-nutrient research is going to illuminate a number of issues with community and self-administered supplementation, but this is speculative on my behalf and may not be true.