Linus Pauling: Various substances are normally present in the human body and many of them required for life and characterized by low toxicity.
I call them orthomolecular substances. Here we have what the Food and Nutrition Board does, estimating the amount, the intake,
needed to keep you from dying. That's the RDA. But you can also ask the question, "What is the intake that will put you in
the best of health? And be most effective against disease." And when I went through the medical, nutritional literature to
find out what this intake was I found there was nothing in the literature about it. Practically nothing, just a few papers
had been written on this subject.
Well, how do you find out? It's a little hard, when people ask me I say, "If you still catch colds you're not taking enough
vitamin C." That's one way of finding out. It's interesting that for most vitamins, all animals require the substances exogenously.
With little doubt what happened was, 600 million years ago, primitive animal was running around eating plants, his ancestors,
these plants. His biochemistry was very much like theirs. Here he was able to synthesize thiamine and riboflavin and peroxygen
and vitamin A. But he was eating the plants which synthesized them and he was getting enough in his foods so that he really
didn't need this apparatus and he lost it. And ever since then, all animals have required these various vitamins.
This didn't happen with vitamin C. And why not? Presumably because there isn't enough vitamin C in the foods. And one reason
that animals require more vitamin C than plants is that animals have collagen as their principal macromolecular molecule,
structural molecule, and plants use a carbohydrate, polysaccharide cellulose. So human beings can't synthesize collagen without
using up vitamin C. They need more vitamin C than animals do so they've kept on synthesizing it. Unfortunately, the common
ancestor of all of the primates some 25 million years ago was living in a tropical valley where the food was so high in vitamin
C that when a mutant came along that had lost the ability to make the enzyme that would produce vitamin C, he had an advantage
over the wild type...and since then, all the primates have had to get vitamin C exogenously. Most of them have had sense enough
to stay in the tropics eating the foods that are high in vitamin C, but man has moved out into temperate and subarctic areas
and has changed his eating habits in such a way that practically all human beings are suffering from a sort of subclinical
scurvy, that is called "ordinary good health," but should be called "ordinary poor health."
So we can ask, how much vitamin C do these animals manufacture? It's proportional to body weight. Seventy kilograms of house
flies manufacture ten grams of vitamin C per day. In general, animals manufacture about ten grams per day. It says here, two
to twenty grams per day per seventy kilogram body weight. That's forty to four-hundred times RDA for humans. I might as well
mention now that I take three-hundred times RDA, eighteen grams of vitamin C per day, and eighty times RDA of vitamin E and
twenty-five times RDA of the B vitamins. Perhaps when I start getting old I'll go up to fifty times, ten times RDA of vitamin
A. It's interesting that the recommended amount of vitamin C is seventy times that for human beings. It's easy to understand
that of course. Monkeys are expensive, probably $1000 each, I don't know, maybe $2000 each. If you've been spending the last
year implanting electrodes in their brains and writing down things in a research book and then come in and the monkeys have
died, that's a real tragedy. You can't publish a paper and you probably won't get tenure. So they've worked very hard to find
out what the optimum intake of vitamin C is for monkeys.