Daidzein

Daidzein structurally belongs to the group of isoflavones.

Natural occurrences

Daidzein and other isoflavone compounds, such as genistein, are present in a number of plants and herbs like Kwao Krua (Pueraria mirifica) and Kudzu (Pueraria lobata). It can also be found in Maackia amurensis cell cultures.

In food sources

Daidzein can be found in food such as soybeans and soy products like tofu and textured vegetable protein. Soy isoflavones are a group of compounds found in and isolated from the soybean. Of note, total isoflavones in soybeans are—in general—37 percent daidzein, 57 percent genistein and 6 percent glycitein, according to USDA data. Soy germ contains 41.7 percent daidzein.

Biological activities

Daidzein can be converted to its end metabolite S-equol in some humans based on the presence of certain intestinal bacteria. Based on several decades of research, S-equol has potential for significant health benefits.

Daidzein has no classification in the United States, where it is not considered to be generally recognized as safe (GRAS), and has not been approved as a drug for any indication. It is a component of foods and dietary supplements derived from soy. Dietary supplements are not regulated as drugs in the U.S., and the labeling of dietary supplements in the U.S. may not describe the supplement as having any drug activity or effectiveness.