In addition, the tubers appear to have numerous health-promoting factors. Hypertensive rats that were fed powdered tubers as 5% of their total diet had a 10% decrease in blood pressure and also a reduction in cholesterol and triglycerides. It has been shown that the tubers contain genistein and other isoflavones that have various health benefits, including an anti-carcinogenic function against colon, prostate, and breast cancer. Genistein-7-O-gentiobioside is a novel isoflavone that is found in the American groundnut. Extract from the American groundnut was shown to drive the anti-oxidative pathway in cells although it did not have anti-oxidative activity itself. Human breast carcinoma MCF-7 cells were pretreated with the extract of "A. americana" for 24 hours. Subsequent analysis showed an increase in expression of heme oxygenase-1, a protein induced during oxidative stress. The American groundnut, like soybean, is a great source of isoflavone.