Vitamin C and the Common Cold: A Comment on the Review by Franklin C. Bing

A review of my book Vitamin C and the Common Cold, by Franklin C.
Bing, was published in the JAMA for 1 March 1971.

I do not object to the expression by the reviewer of his opinions. I
feel, however, that it is essential that the several untrue statements and
thoroughly misleading statements that he makes be corrected.

The author states that ''Unfortunately, many laymen are going to be-
lieve the ideas that the author is selling--that ascorbic acid is a completely
harmless chemical which will prevent or mollify infectious diseases such as
the common cold, if taken in doses of from one to ten gm daily throughout
life, and possibly extend that lifetime from two to six years. '

In fact, I do not state that ascorbic acid is a completely harmless
chemical. I describe it as a natural, essential food that is nontoxic, and has
far fewer side reactions than aspirin and other common cold medicines.

I do not recommend taking doses of from one to ten grams daily
throughout life. Instead, I say that there is evidence that some people re-
main in very good health, including freedom from the common cold, year
after year through the ingestion of only 250 mg of ascorbic acid per day,
that the requirements of a few people for ascorbic acid may be expected to
be even smaller, that for many people one gm to two gm per day is approx-
imately the optimum rate of ingestion, and that for some people optimum
health may require larger amounts, up to five gm per day o# more.

The reviewer states that ‘Actually, when used as recommended by
Professor Pauling, neither the safety of all dosage forms, nor the efficacy
of ascorbic acid in any dosage form, has been proved. ''

In fact, I compare the evidence about the safety of ascorbic acid with
that of the usual cold remedies, and conclude that the usual cold remedies
are more dangerous than ascorbic acid.

Also, I present in my book a careful analysis of the controlled trials
of ascorbic acid that have been published, and point out that several of these
investigations have shown, with statistical significance, at the confidence
level of 95 percent or higher, that ascorbic acid has value in decreasing both
the incidence and the severity of the common cold. There has been no con-
trolled study that has shown, with statistical significance, that ascorbic acid
~ 2.

administered regularly to a population exposed to cold viruses in the normal
way does not have the amount of protective value that I describe for it, in
my book.

The author states that ‘In reviewing published reports, Pauling ex-
plainas negative findings by implying that positive results would have been
obtained if larger doses of vitamin C had been employed. '' This statement
is thoroughly misleading, in that it is correct only if it is applied to the
published reports of investigations in which vitamin C was given to patients
who had already contracted colds, or who had been subjected to the unusual
ingult of inoculation with large doses of cold viruses. The several published
reports of controlled studies in which ascorbic acid is compared with a
placebo, with both given during a period of time beginning before colds had
been contracted and with subjects exposed to cold viruses in the normal WY,
have led to the statistically significant conclusion that ascorbic acid has pro-
tective value; that is, they have given positive results, rather than negative
results. No controlled trials of this sort have given negative results with
statistical significance, and it was not necessary for me to explain any nega-
tive findings for studies of this sort.

The reviewer states thet ‘Pauling hopes that there will be a thor-
ough, large-scale study on vitamin C and the common cold. Because he
has already convinced himself that vitamin C in large doses does avert or
ameliorate the common cold, the question arises: what kind of research
does he have in mind? '

Here the reviewer has thoroughly misrepresented my statements,
presumably because he has been careless in reading the book. On page 61
I eay ‘So far as I am aware, no large-scale study, involving several hundred
or thousand subjects, has been carried out to show to what extent the regular
ingestion of ascorbic acid in large amounts is effective in preventing and
ameliorating the common cold and associated infections. I hope that some
such large-scale studies will be carried out; but in the meantime I am con-
vinced by the evidence already available that ascorbic acid is to be preferred
to the analgesics, antihistamines, and other dangerous drugs that are recom-
mended for the treatment of the common cold by the purveyors of drugs. '

I emphasize that I stated in my book that no large-scale study has been
carried out to show to what extent the regular ingestion of ascorbic acid in
large amounts is effective. The reviewer misquoted me, by omitting the
statement about regular ingestion in large amounts. In fact, large-scale
studies involving the regular ingestion of ascorbic acid in small amounts
have been carried out, and have given statistically significant results, showing
that even these small amounts are effective in preventing and ameliorating the
common cold and associated infections. The carelessness of the reviewer
is made clear by the fact that on page 51 the sentences immediately pre-
ceding the sentences quoted above are the following: ‘In this chapter !
have discussed some of the investigations that have been carried out on
ascorbic acid in relation to the common cold; others are discussed in
Appendix III. Some of these investigations have been well designed but,
unfortunately, have involved the use of rather small quantities of ascorbic
acid, and have shown only that these rather small quantities have limited
value in preventing or ameliorating the common cold."

I find it astonishing that the reviewer should misrepresent my book
so thoroughly, and that he should give the readers of the Journal of the
American Medical Association the impression that there have not been any
thorough, large-scale studies of vitamin C and the common cold, when I
had included a detailed discussion of several such studies in the book that
he was reviewing.

A correct review would have included mention of the fact that sev-
eral good controlled studies have been made of the effect of ascorbic acid
in amounts of about 200 mg per day or 1, 000 mg per day administered reg-
ularly to subjects, beginning before they had contracted colds, with other
subjects receiving a placebo, and that it had been found that the ascorbic-
acid subjects had fewer colds than the placebo subjects, that the severity
of individual colds was less, and that these results were statistically aig-
nificant.

An example of such a careful double-blind controlled trial carried
out by reliable and experienced medical investigators is that of Drs. Cowan,
Diehl, and Baker, reported in the JAMA for 1942. This investigation was
described by Dr. Haven Emerson of New York as a good example of a care-
fully controlled study. '' The authors reported that they had found a 15-per-
cent smaller incidence of colds in the ascorbic-acid group than in the placebo
group, and that this difference is statistically significant, the probability that
it would occur through a statistical fluctuation in a uniform population affect-
ed equally by the ascorbic acid and the placebo being only 3 or 4 percent.
They also reported that the average number of days of iliness for the ascor-
bic-acid subjects was $1 percent less than for the placebo subjects. This
difference ia also statistically significant, at the l-percent level. The
amount of ascorbic acid given was about 200 mg per day.

Another very careful double-blind controlled atudy deacribed in my
book was reported by Dr. G. Ritsel, of the public school health service in
Basel, Switzerland. In this investigation the subjects received 1, 000 mg of
ascorbic acid per day, with the control subjects receiving a placebo. The
detailed account of the work published by Dr. Ritzel in Helvetica Medica
Acta for 1981 shows the care with which it was carried out. The incidence
of colds for the ascorbic acid group was 45 percent less than that for the
placebo group, with statistical significance at the 1-percent level. The
total number of days of illness from upper respiratory infections was 61
percent lesa for the ascorbic-acid subjects than for the placebo subjects,
and the incidence of individual symptoms was 65 percent lesg for the as-
corbic acid subjects than for the placebo subjects. The author reports
that statistical analysis by an independent team of statisticians showed that
these differences had statistical significance at the 1-percent level.

The reviewer's statement that the efficacy of ascorbic acid in any
dosage form has not been proved is false. Results with high statistical
significance obtained by reliable medical investigators in carefully con-
trolled studies, such as the two quoted above, have proved the efficacy
of ascorbic acid, administered over a period of time to subjects exposed
to cold viruses in the normal way, in decreasing the incidence and sever-
ity of the common cold, and these results have not been contradicted by
statistically significant negative resulta in a single controlled test carried
out under similar circumstances.

The review of my book misrepresents the facts completely.

Linus Pauling