Science Marches On (Over Linus Pauling's Dead Body)

Gather 'round, dear readers, and let me regale you with the sad saga of the late, great Linus Pauling.

On second thought, calling it "sad" might be a bit excessive. Pauling was the only person to win two individual Nobels, after all (one for chemistry, one for peace). His great achievements are too numerous to fully list here; suffice to say he was a pioneer in molecular biology, genetics, immunology, the nature of chemical bonds and scientific activism. But by his death in 1994, many in the scientific community regarded him as an embarrassment, an out-of-touch quack at best and a dishonest shill of the health supplement industry at worst.

What happened?

In essence, he challenged the established notions of nutrition, particularly regarding vitamin C. Pauling was influenced by the work of biochemist Irwin Stone, who pointed out that the majority of plants and animals produce their own vitamin C in proportion to their bodyweight, with humans, apes and a handful of other (primarily fruit-eating) species being the rare, incapable exceptions due to a purported genetic defect. Pauling reasoned that since vitamin C is present in most animals in concentrations vastly greater than the amount most people consume each day, some common illnesses might be the result of this perpetual vitamin C deficiency.

Consequently, he proposed that "megadoses" of vitamin C could effectively treat several illnesses, most notably cancer and the common cold, and published a few books to popularize these ideas. In 1973, he formed the Linus Pauling Institute of Medicine, where he performed multiple experiments to verify his claims.

The real trouble started when other researchers tried--and failed--to replicate his results. Despite exhaustive examination, today the efficacy of vitamin C as a cold and flu treatment remains questionable. Three successive studies by the prestigious Mayo Clinic testing orally administered vitamin C demonstrated no significant cancer-fighting effects. Additionally, it was revealed that Hoffman-La Roche, a company that at the time produced most of the world's vitamin C supplements, extensively funded Pauling's Institute. Naturally, all this damaged his credibility and he was relegated to the fringes of science in the twilight of his life.

Fortunately for poor old Pauling, this story might yet have a happy ending. Two papers published in the last year are forcing a re-appraisal of vitamin C's effects on cancer. The first, from the September 20th, 2005 Proceedings of the National Academy of Sciences, found that vitamin C selectively killed various cancer cell types, leaving normal cells unharmed, but only when in serum concentrations achievable solely via intravenous administration.

The second study, published in the March 28th, 2006 Canadian Medical Association Journal, presented 3 well-documented cases where intravenous injections of very high doses of vitamin C had apparently extended the lives of advanced cancer patients. An accompanying commentary should temper any pro-Pauling optimism with its discussion of spontaneous remission rates and unknown sample sizes, but it leaves the question open and the door cracked for further inquiry.

It's curious - if Pauling's original experiment demonstrating vitamin C's anti-cancer effects was based on both oral and intravenous vitamin C supplementation, why did the subsequent studies attempting to "replicate" his findings forego testing both routes? When they couldn't replicate Pauling's results, why wasn't their methodology challenged? It seems increasingly plausible that if anyone had bothered to notice and correct these fundamental oversights, Pauling's reputation would have been redeemed and a potentially valuable cancer therapy might have gained mainstream acceptance much sooner.

The frightening implication of all this is, if it somehow happened to one of the greatest figures of 20th century science, it can certainly happen to anyone who speaks out about the credibility of unorthodox ideas. For instance, without the benefit of these recent studies, a science journalist writing about Pauling's vitamin C theories without calling them baloney and flapdoodle would likely have been a target for professional derision and ridicule - and perhaps still will be.

But perhaps instead the ultimate vindication of a great mind's last discovery is at hand. And hopefully, Pauling's tragic downfall and unfolding redemption will provide a valuable lesson in science's fallibility for those who truly seek objectivity.