I got a comment that I'm not going to publish. My decision is not because the commenter is wrong -- people can be wrong and we can discuss it -- but that the person is offensively strident. However, I will tell you that she or he believes that Linus Pauling was right about megadoses of vitamin C. He wasn't, and that provides a perfect illustration for what I was already planning to say next. I'll quote from Sarah Harrison, writing in the Science History Institute's magazine Distillations:
Pauling had conducted none of the studies his vitamin C theories were built on. Human drug trials are large and expensive to run. So instead, Pauling’s claims were based on the review of existing literature and the experiments of others. This invited problems, such as flawed data. The trials Pauling relied on had inconsistencies between study groups that made the placebo and the vitamin C groups nearly impossible to compare.
Despite his brilliance, Pauling was ill-equipped to catch these errors.Pauling biographer Ted Goertzel points out that nutrition research isn’t quite like chemistry. There are many more variables to consider in a human trial than with isolated molecules in a lab. What is the dosage of the supplement? When and how is it administered? The study participants themselves add complications: their age, health, or the strength of their immune systems can all differ. Their lives and activities outside the lab can affect the results too.
“His vast knowledge was specialized,” says Goertzel. “He had tremendous knowledge on molecular structure and chemistry. But that doesn’t mean you have a tremendous knowledge about nutrition and vitamins and health.”
And Pauling’s interpretations were questionable. He emphasized the positive effects he saw while explaining away negative or weak results as flaws in study design. Pauling’s vitamin C research was full of cherry-picked data that he wove into a narrative that suited his hypothesis, a process Goertzel likens to the logic of conspiracy theories.
“You get selective evidence, and you throw something out and insist that other people disprove it, and if they can’t disprove it, it might be true,” he says.
Pauling’s approach to vitamin C had none of the rigor or peer review that characterizes good science. When other scientists criticized his articles in peer-reviewed journals, Pauling took his case straight to the public. In 1970 he published Vitamin C and the Common Cold. Written for general audience, the book extolled the virtues of megadoses of ascorbic acid using little more than anecdotal evidence.
That tees up the next post. Note the main point here: Pauling was a chemist, who started pontificating about human biology. That's where he went wrong. I'll get to the point in the next post.