Chicken soup isn't just good for the common cold and, apparently, our souls, that popular home remedy so ubiquitous it is sometimes known as "Grandma's Penicillin" may also have a new role alongside medication and other medical measures in fighting high blood pressure, scientists in Japan are reporting. Their research is in the Journal of Agricultural and Food Chemistry.

Ai Saiga and colleagues cite previous studies indicating that chicken breast contains collagen proteins with effects similar to ACE inhibitors, mainstay medications for treating high blood pressure. But chicken breast contains such small amounts of the proteins that it could not be used to develop food and medical products for high blood pressure. Chicken legs and feet, often discarded as waste products in the U.S. but key soup ingredients elsewhere, appear to be a better source.

In the new study, Saiga and colleagues extracted collagen from chicken legs and tested its ability to act as an ACE inhibitor in the laboratory studies. They identified four different proteins in the collagen mixture with high ACE-inhibitory activity. Given to rats used to model human high blood pressure, the proteins produced a significant and prolonged decrease in blood pressure, the researchers say.

Article: Ai Saiga, Koji Iwai, Toru Hayakawa, Yoshihisa Takahata, Shiniich Kitamura, Toshihide Nishimura, and Fumiki Morimatsu, 'Angiotensin I-Converting Enzyme-Inhibitory Peptides Obtained from Chicken Collagen Hydrolysate', J. Agric. Food Chem., ASAP Article, 10.1021/jf072669w