Vitamin C and the Immune System

The body’s immune system is a medical marvel still not
fully understood by man. But we know that when it operates
properly, it keeps us well. Now, research done by four South
African doctors has revealed some important new data on the
beneficial effect of vitamin C on certain parts of the immune
system. The research showed that vitamin C supplementation

‘raised the concentration in the blood of IgA (Ig is an abbrevi-
ation for immunoglobulin), IgM, and the C3 complement
component—three key members of the immune system

To understand the importance of these results, some back-
ground in the functions of the immune system may be use-
ful. This system is the body’s self-defense force. It patrols the
body like a mobile army, protecting against foreign invaders
such as bacteria and viruses. It will either attack these in-

vaders directly or utilize “mercenary troops” to aid in their

disposal. -

There are several parts to the im-
mune system, each with a different
function. Three of the most important
immunoglobulins are IgA, IgM, and
IgG. IgA antibodies are found mainly
at the surfaces of the openings of the
body. Moist surfaces, such as the
mouth, are covered with IgA anti-
bodies ready to attack invading bac-
teria or viruses and prevent them from
entering our system through these
openings.

IgM antibodies are the first to re-
spond to the intrusion of antigens (the
enemy cells which trigger the antibody
response) and serve as the means of
activating additional parts of the im-
“mune system to join in the fight.

IgG antibodies make up the largest
percentage of antibodies in the blood,
about 70%, and they are very effective
in protecting the body from viral in-
fections. IgG is the most important
class of antibodies that crosses the
Placenta from an immunized mother
to her fetus and thus provides early
antibody protection for the newborn
infant until the baby-can produce his
own antibodies.

The complement system, with nine

components labeled C1 through C9, is activated by the pres-
ence of other immunoglobulins and is very important in the
destruction of antigens. C3 is one of the most important of
the complement components.

The experiment in South Africa was conducted to de-
termine if quantitative evidence could be found to support
the theories of Linus Pauling and others about the benefits of
vitamin C in preventing colds. Since the nature and severity
of colds is so subjective, it was felt that stronger and more
valid evidence would come from the measurement of certain
parts of the body’s immune system, which could be done
objectively.

The study was conducted with 45 volunteers, all of whom

" were healthy nonvegetarians who had not: previously been

exposed to extraordinary doses of vitamin C. They were di-
vided into two sections, 20 in the control group and 25 in
the experimental group (five extra experimental subjects
were chosen in anticipation of dropouts which did not oc-
cur). The test period extended over 11 weeks, during which
time all subjects adhered to their regular diet and the mem-
bers of the experimental group ingested 1,000 milligrams of
vitamin C daily. Blood samples were taken from all partici-
pants before the study began and again at the end of the test
period.

The blood samples were given a blind coding to avoid any
influence of investigator bias, and the serum levels of the
various antibodies were determined. The positive results of
the study were as follows:

The experimental group showed an increase of 20% in
serum IgM levels relative to the control group. In the case of
C3, the experimental group levels increased 15% as opposed
to a slight decline in those of the control group. Those receiv-
ing vitamin C supplementation had a rise in their IgG levels,
but the degree of increase was not statistically significant.
The vitamin C group showed no change in their serum IgA
levels, but the control group showed a decline of 15% in
theirs. This result was unexpected and hard for the re-
searchers to explain, but they thought possibly that the IgA
levels of the experimental group would have declined like
those of the control group, had they not received vitamin C.

Continued on following page .
132

It is important to note that the
study began on July 2 (early winter in
the southern hemisphere) and, since
IgA is the principal immunoglobulin in
mucous secretions, the secretory drain
of IgA may be subject to seasonal vari-
ation. It is implicit in this reasoning
that vitamin C acts in some way to
counteract a potential net decrease in
serum levels in the winter.

The decline in IgA levels in the con-
trol group during the period from ear-
ly winter to early spring points out
that you may be wise to increase the
amount of vitamin C in your diet dur-
ing these months to combat this po-
tential decline (as discussed in the arti-
cle that follows). The lowering of IgA
levels may also explain why there are
sO many more viral infections during
the winter and spring.

In summary, the study found that
‘vitamin C supplementation had a bene- ©
ficial impact on the serum levels of
IgA, IgM, and C3—in effect, strength-
ening some important parts of the
body’s immunological system.