Of course, there CAN be a medical need. I worked with a PhD Nutritionist some years ago and he was publishing papers about the advantages of getting surgery patients pumped up with nutrients, vitamins, and minerals before you did the surgery. He found some pretty significant results, in terms of mortality.
I have idiopathic neuropathy, and so I've had a nerve conduction study and a peripheral blood flow study done.
Nothing indicative of a problem, just demylination. That's why it's idiopathic. I've read about some legitimate doctors who have found B vitamins, lipoic acid, and probiotics help combat some of the causes. Likewise, non-symptomatic Celiac Disease can also contribute to demylination. So I have also had a Celiac antibody test, and I'm taking B-50 and lipioc acid.
Before I start taking anything, I read a lot of peer-reviewed papers on that substance. You need a good BS filter what with all the snake-oil salesmen and Big Pharma pushing all their wonder drugs.
My latest discovery is that a mix of Chinese herbs is being marketed as Protandim, with a pyramid marketing scheme for several hundred dollars per year. It might actually be more effective at controlling the Nrf2 metabolic path than Tecfidera ($70K+ per year). But the recipe is out there: You can buy the individual herbs and make it yourself for about $50 per year!