Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Vitamin C offers little protection against colds

18.07.2007
Unless you run marathons, you probably won’t get much protection from common colds by taking a daily supplemental dose of vitamin C, according to an updated review of 30 studies.

Conducted over several decades and including more than 11,000 people who took daily doses of at least 200 milligrams, the review also shows that vitamin C (ascorbic acid) does little to reduce the length or severity of a cold, according to the researchers at the Australian National University and the University of Helsinki.

However, they found that people exposed to periods of high stress — such as marathon runners, skiers and soldiers on sub-arctic exercises — were 50 percent less likely to catch a cold if they took a daily dose of vitamin C.

For most people, the benefit of the popular remedy is so slight when it comes to colds that it is not worth the effort or expense, the authors say. “It doesn’t make sense to take vitamin C 365 days a year to lessen the chance of catching a cold,” said co-author Harri Hemilä, a professor in the Department of Public Health at University of Helsinki in Finland.

The review appears in the latest issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.

Since the discovery of vitamin C in the 1930s, controversy regarding its efficacy in treating ailments from lung infections to colds has surrounded it. In the 1970s, Nobel Prize-winning chemist Linus Pauling popularized its regular use. His book, “Vitamin C and the Common Cold,” encouraged people to take 1,000 milligrams of the vitamin daily.

The current recommended daily allowance of vitamin C is 60 milligrams. An eight-ounce glass of orange juice has about 97 milligrams of vitamin C.

Despite early mixed results and later evidence against its efficacy, charismatic Pauling became the world’s vitamin C champion. “Pauling never recanted and never backed down,” said Wallace Sampson, founding editor of the Scientific Review of Alternative Medicine and emeritus professor of medicine at Stanford University.

Regardless of the evidence against it, vitamin C remains popular because many people —including those funding studies — want to believe that it works, said Sampson, who debated Pauling on the radio and in letters.

These days, there is less interest in studying vitamin C and the common cold, said Hemilä, who has studied the vitamin for more than 25 years. The Cochrane Review was originally published in 1998 and updated in 2004 and this year. The latest update includes a single new study on the Vitamin C-cold connection.

However, researchers continue to examine vitamin C alone and in combination with other vitamins and substances, such as Echinacea, for its efficacy in preventing and treating diseases and conditions, including cancer. This is not necessarily a good thing, Sampson said. “It’s broadside quackery.”

Hemilä said he sees little use in further study for colds for adults. However, he would like to see more studies on vitamin C and colds in children and vitamin C and pneumonia. Vitamin C is not a panacea, but it is not useless either, Hemilä said. “Pauling was overly optimistic, but he wasn’t completely wrong.”

Lisa Esposito | EurekAlert!
Further information:
http://www.cfah.org
http://www.cochrane.org

More articles from Health and Medicine:

nachricht One gene closer to regenerative therapy for muscular disorders
01.06.2017 | Cincinnati Children's Hospital Medical Center

nachricht The gut microbiota plays a key role in treatment with classic diabetes medication
01.06.2017 | University of Gothenburg

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>