By comparison, the average level of the soy
isoflavone genistein in the bloodstream of Asian women is approximately 25 nanograms per milliliter, but in U.S. women, only 2 nanograms.
Research out of the University of Maryland and reported in the Journal of Agriculture and Food Chemistry found that quail feed supplemented with the soy
isoflavone genistein ended up in the egg yolk but not the egg white.
In recent studies, rats fed
the isoflavone genistein exhibited pathological changes in the colon23 and rats fed soy - based chow had reduced growth and an increase in gastrointestinal problems.40
See: Interaction of estrogenic chemicals and phytoestrogens with estrogen receptor β Soy
isoflavone genistein has about 4 % of 17β - estradiol's affinity for estrogen receptor α, responsible for estrogen's feminizing effects, and 87 % of its affinity for ERβ, which acts as a tumor suppressor.
Finally the soy
isoflavone genistein reduces DNA synthesis in the brain, reducing the birth of new brain cells and promoting apoptosis and cell death.
Direct evidence that soy
isoflavones genistein and daidzein suppress the pituitary - thyroid axis in middle - aged rats fed 10 mg soy isoflavones per kilo after only 3 weeks as compared with rats eating regular rat chow.
These studies — which include analysis of
the isoflavones genistein, daidzein, malonylgenistin, and malonyldaidzin — show a limited impact of soy food intake on thyroid function, even when soy isoflavones are consumed in supplement form at levels higher than expected from food.
Soy is loaded with
the isoflavones genistein and daidzein.
Not exact matches
Soybeans are the most common source of
isoflavones and the major
isoflavones in soybean are
genistein and daidzein.
Of the two main
isoflavones,
genistein and diadzein, the former seems to be more effective in preventing osteoporosis.
One of soy's primary
isoflavones,
genistein, has been shown to inhibit the enzyme tyrosine kinase in the brain.
Soy contains many types of
isoflavones, but the most beneficial are
genistein (see picture) and daidzein.
Miso, a fermented or probiotic form of soy bean, is particularly rich in the
isoflavone aglycones,
genistein and daidzein, which are believed to be cancer preventatives.
Fermentation increases the digestibility of soy (especially its proteins), nutrient absorption from soy (including absorption of phytonutrient
isoflavones like
genistein and daidzein), and the concentration of bioactive peptides (formed during the breakdown of soy proteins during fermentation).
Dr. Pepine and his colleagues had expected that women with high levels of
genistein (the primary
isoflavone found in soybeans) would show improved vascular health, but found the opposite to be true.
The main
isoflavone in soy,
genistein, deactivates human thyroid peroxidase (TPO), an enzyme, and interferes with T3 and T4 synthesis.
Soy is rich in
isoflavones, particularly
genistein, which is a type of phytoestrogen.
It has been argued that high levels of soy
isoflavones such as
genistein, daidzein and genistin in Asian diets protect the inhabitants of Japan and China from certain degenerative diseases, especially breast and prostate cancer.
The unsweetened soymilk and tofu do not cause much flatulence and they retain most of the health benefits of eating soybeans, including the
isoflavones,
genistein, daidzein, and glycitein.
The first recognized antioxidants were vitamin C and vitamin E, but other substances that have powerful antioxidant properties have also been recognized: Selenium, Carotenoids (Beta - carotene, Lutein, Lycopene, Sulforaphane, Zeaxanthin, and Astaxanthin), Bioflavonoids (Anthocyanins, Proanthocyanidins, Quercetin, and Apigenin), Coenzyme — Q10 (Co — Q10), Soy
Isoflavones (
Genistein and Daidzein), and many other less well - known compounds found in fruits and vegetables.
No phytonutrient in soy has received more widespread attention than
genistein — an
isoflavone that has been extensively studied in relationship to cancer risk.