4Life Research's "Transfer Factor Plus" or TF+ raised NK (Natural Killer) cell activity by an un-precedented 248% in Independent tests.
This was the highest performer compared with 196 other Natural products. This is a landmark study undertaken over 6 years and published in 1998, and compares "apples with apples". 4Life's Transfer Factor Classic (as it is now called) - a product still available in Australia also beat the 196 products, coming second to the flagship Transfer factor Plus product.
Note: In later test published in 2003, the new Transfer factor Plus Advanced formula raised NK cell activity by 437%.
See the results chart below, and click here to read the impressive amounts of scientific and medical research and findings on transfer factor.