Hoffer came up with a unique definition of "natural" substance - one that was already present in the body. There are roughly a few dozen of these that we cannot make and have to eat and although required in small doses for optimal health there is a growing belief that the comparatively miniscule doses based on early 20th century research are too low for some individuals and historical levels of these nutrients as in pre industrial society should be the goal.

Mankind has sen a slow and steady progression of unexplainable fatal chronic disease cured by remediating specific micronutrient deficiencies: scurvy 300 years ago in Europe, beriberi in the late 1910s, and as recently as the 1920s in the United State when pellagra broke out with 3 million cases and 100,000 deaths before we began enriching all flour with vitamins. These were deficiencies in the vitamins C, B1 and B3 and government established minimum daily requirements that would prevent death.

The problem is they were not the amounts for optimal health. It had been suggested that they don't really work but in every case if you "follow the money" it's traced back to a pharmaceutical company in every case, without exception.

Ascorbate is used widely in the food industry (as is tocopherol, vit E) as a preservative. Because it's a chemical the body needs and has a amechaimsm to flush any axcess it's a good choice. Ask yourself why do they use trace amounts of poisonous crucial to preserve vaccines, why don't they use ascorbate? Because when they tried that it killed the virus.

Ref:
http://en.wikipedia.org/wiki/Pellagra