Have you heard about that 'novel' antidepressant agomelatine?
(Melatonin on the left, agomelatonine on the right)
It's just our endogenous melatonin with the indole replaced by naphthalene - because they couldn't patent melatonin as a natural molecule. The side effect of this little modification is that the agomelatine is ridiculously hepatotoxic, elevated liver enzymes are common & there have been liver failures due to this medication - and it has a half life of just 1-2 hours!! Now imagine having this 24/7 in your system, and say your liver goodbye ... it is approved in the states, in the EU, probably in other countries ... the AD effects are disputed. The effects for sleep are also somewhat disputed afaik (melatonin works for jet lag / shift workers, but not always & not instantly like your usual sleeping pill). But the damage is real - and the revenue.
Melatonin is available dirt cheap without a script in many countries, but docs continue to prescribe agomelatine ... I know they have a hard time to catch up with all the news and the workload etc, but something's definitely going wrong.
About that Vitamin C stuff I don't know.. there are many myths that contain some truth, but I'm cautious with them.. I believe in true science, and common sense (which seems to be chronically out of stock these days) ...
Funny that the states, being THE leaders in prohibition & war on drugs, have legalized pot now. It's a step in the right direction, but by far not enough and the UN continues to prohibit.. as well as the EU.. the alcohol thing has traditional / cultural / historical reasons, but it's crazy illogical yes..