Data from clinical trials looking at both infection and responses to vaccinations indicated that arabinogalactan from North American Larix species (Larix laricina and Larix occidentalis) could benefit immune health in humans.
“Therefore, these results suggest a role for larch arabinogalactan in the improvement of immune system and defense against pathogens in humans,” wrote the authors in Nutrition & Metabolism.
“It is interesting to note that both models (infection and vaccine) are considered relevant by the European Food Safety Authority (EFSA) to substantiate health claims on immune system in the frame of European regulation (EC) 1924/2006 on nutrition and health claims.”
The review was performed by Carine Dion, Eric Chappuis and Christophe Ripoll from Naturalpha, an international consulting, scientific and clinical research company based in France. The review was funded by Lonza, which supplies the ResistAid-branded larch arabinogalactan.
Review details
The reviewers assessed data from cell, animal and human studies. The cell and animal data indicated that larch arabinogalactan may enhance natural killer cells and macrophages. The ingredient may also enhance the secretion of pro-inflammatory cytokines.
Data from one human clinical study examining the incidence of cold episodes found that Lonza’s ResistAid product could reduce cold episodes by 23%, compared to placebo (Current Medical Research and Opinion, 2013, Vol. 29, pp. 251-258).
Data from human studies using Streptococcus pneumoniae and tetanus vaccinations indicated that serum antigen-specific IgG and IgE responses improved, suggesting an immunostimulatory effect.
“To explain the mode of action, it has been suggested that it can interact with the immune system either indirectly through the production of SCFAs [short-chain fatty acids] that affect inflammatory responses via leukocytes function and cytokine production, or directly through the capacity of M-cells to transfer intact arabinogalactan through the intestinal barrier, delivering it to immune cells,” wrote the authors.
“However, the exact mode of action is not yet completely understood and further studies are required to better understand it and define more precisely the benefits of larch arabinogalactan to the immune system.”
Source: Nutrition & Metabolism
2016 13:28, doi: 10.1186/s12986-016-0086-x
“Does larch arabinogalactan enhance immune function? A review of mechanistic and clinical trials”
Authors: C. Dion, E. Chappuis, C. Ripoll