|
Wednesday, July 27, 2005
Vitamin C studies disprove rationale for daily use
By Zosimo T. Literatus, R.M.T.
While lessons in history can teach a lot in helping solve present woes, some lessons need to be restudied to make sure that they actually work today.
This truth applies to the historically accepted assumptions regarding vitamin C. Can it actually prevent or treat the common cold?
Most people believe that vitamin C supplements boost the immune system and ward off illness, an idea that gained great popularity during the 1970s, thanks to famous chemist and Nobel laureate, Linus Pauling. But a recent large-scale study reviewing 55 studies relating to vitamin C, carried out over 65 years, shows that prophylactic use of this vitamin in everyday circumstances has little effect.
The study, conducted by Robert Douglas of the Australian National University (Canberra, Australia) and Harri Hemilä of the University of Helsinki (Helsinki, Finland), reviews the literature to “discover whether vitamin C in doses of 200 mg or more daily reduce the incidence, duration, or severity of the common cold when used either as continuous prophylaxis or after the onset of cold symptoms.” The study was sponsored by the National Centre for Epidemiology and Population Health of the Australian National University in Canberra, Australia.
Pooled data on the many studies in the review - involving literature from 1940 to 2004 all methodically screened - that asked whether vitamin C reduces the incidence of the common cold showed no significant protective effect overall.
They also found that use of the vitamin reduced the duration of colds by only eight percent in adults and 14 percent in children. This, the researchers say, provides poor justification for everyday mega doses of the nutrient.
According to Hemilä, most adults catch only one common cold a year. Taking supplements every day to avoid this makes little sense, he says. The results of the study have been published online on June 28 in the Public Library of Science Medicine.
“There is little doubt,” says Douglas, “that vitamin C has some biological impact.
Although in the main it is nothing like what Pauling predicted and has little place in therapy.”
But the researchers found that marathon runners, skiers and soldiers exposed to icy conditions or physical stress experienced a 50 percent reduction in colds, thanks to the vitamin.
While the results of this study may have contradicted a most accepted notion - or perhaps what we were made to accept for a long time, that vitamin C is effective against common cold in normal daily conditions - it is interesting to know it appears to support our body against extreme icy temperatures and physical stress. We need more a health ally in desperate conditions than otherwise, don’t we?
(July 27, 2005 issue)
Write letter to the editor.Click here.
Join the Sun.Star message board.Click here. |
|
[return to top]
[home]
[network page]
|
LOCAL NEWS
BUSINESS
OPINION
SPORTS
LIFESTYLE
FEATURE
SUPERBALITA
WEEKEND
|
