Antioxidant wood extract shows immune benefits

An antioxidant larch bark extract reduced cold episodes 23% compared to placebo, a German study has found.

Published in Current Medical Research and Opinion, the study that used a Lonza-branded ResistAid larch arabinogalactan version, also found those who suffered no cold incidents was higher in the study group (91.2%) compared to the placebo group (88.5%).

The study conducted by German consultancy, analyze & realize, featured 199 healthy adults aged 18-70 who reported at least three colds in the previous six months.

Placebo groups took either a 4.5g daily larch arabinogalactan supplement of or a placebo for 12 weeks.

Participants recorded common cold episodes in a diary and rated 10 predefined infection symptoms. The episodes were all confirmed by doctors.

“The present study demonstrated that larch arabinogalactan increased the body’s potential to defend against common cold infection. While the immunomodulatory effect of arabinogalactan can be assumed, its mechanism of action remains to be elucidated,” the researchers said.

After publication, a Lonza spokesperson said the study was a breakthrough for the ingredient and would be used as a global marketing tool.

Source: Current Medical Research and Opinion

March 2013, Vol. 29, No. 3 , Pages 251-258, doi:10.1185/03007995.2013.765837

‘Larch arabinogalactan effects on reducing incidence of upper respiratory infections’

Authors: L Riede, B Grube, J Gruenwald