Anti-cancer supplements need plant-based proteins to be effective

In the 1980s manufacturers developed new types of feed for lab animals that were intended to improve the quality of research. These new feeds no longer contained substances of plant origin. And suddenly the findings from animal studies that had used the new feed showed that all kinds of substances that offer protection against cancer were no longer effective.

In 2004 researchers at the University of Alabama at Birmingham published the results of a series of experiments which made it clear just how strong the effect of feed was. Although the researchers addressed their conclusions to fellow animal researchers, their findings are relevant to everyone who uses supplements for protection against cancer.

In their experiments the researchers used 4%-Teklad feed [which contains proteins obtained from various sources including wheat, soya and barley] and AIN-76A feed [which contains only casein-based proteins]. So AIN-76A feed contains none of the plant-based proteins, which, since the 1980s, we know have an effect on the body.

The researchers tested two preparations that contained protective compounds. One was pure genistein, a soya isoflavone. The other was grape seed extract, a preparation from grapes that contains catechins. The researchers gave the preparations to female rats that had been injected with substances that cause breast cancer, and then observed whether the preparations inhibited tumour growth.

In the figures below the white triangles represent the rats that got no genistein in their feed; the white diamonds represent the rats that got feed with 0.8 percent genistein; and the black squares represent the rats that got food containing 1.6 percent genistein. The carcinogenic substance was MNU. The figure immediately below shows the results for the AIN-76A group; the one under that shows the results for the Teklad group.