Azuki-bean saponin improves the blood flow
In order to maintain the flow of blood normal, it is important to keep in mind to avoid the arteries to get clogged. One ingredient that keeps the blood flow smooth is saponin, a compound called glucoside in which sugar and other substances are bonded.
It suppresses cholesterol and neutral fat formation in your body, and so does peroxilipid generation to prevent arteriosclerosis.
Pulses such as Azuki beans and soybeans contain plenty of saponin, which is soluble in water. Saponin can dissolve out largely into the cooking water, mostly the lye in particular, when beans are boiled. Therefore, it is better not to skim off the lye too much when boiling beans. If you take saponin excessively, however, it may increase the chance of enlarging the thyroid gland.
Indigestible starch of boiled Azuki beans lowers the total cholesterol in the serum
Soluble dietary fiber (SDF) has the effect of lowering LDL cholesterol. It also acts to bring down the blood pressure as well as to suppress a rapid elevation of blood sugar level.
In addition, late studies have revealed that indigestible starch (resistant starch) contained in boiled Azuki beans has the function of lowering the total cholesterol in the serum.
Besides saponin and dietary fiber, polyphenols such as anthocyanin also improve the blood flow. Surprisingly, Azuki beans contain less anthocyanin, which is the red pigment component of the seed coat, than black soybeans and red kidney beans do.
Contrary, Azuki beans contain abundant other polyphenols as great antioxidant resources, which demonstrate the power to lower LDL cholesterol and to improve the blood flow.
Written by Jun Kato PhD.
Source from 『「あずき」のチカラはこんなにすごい！』
Translated by Azusa Yoshida.