Is breast milk blood?

I often hear people from the older generation say that mother's breast milk is the blood in the body, which is converted into breast milk and then fed to the baby, so mothers are very great. Milk is not necessarily blood, and breast milk is not converted from blood. Although the blood and the mammary glands of the breast are connected, this is not breast milk converted from blood. We need to have a correct understanding and knowledge of this, and carefully judge the normal structure of breast milk.

The fallacy that "milk is transformed into blood" has been circulating for a long time. What is the reason?

In the West, people have observed that many breastfeeding women experience amenorrhea. So, they believe that human breast milk is converted from menstruation. Leonardo da Vinci expressed this idea in one of his paintings: a woman's breasts and uterus are connected by a tube.

In the East, there are more records of blood turning into milk, some of which have even been compiled into classics. At the end of the Northern Song Dynasty, Emperor Huizong ordered the Imperial Hospital to compile the "Shengji Zonglu", which recorded: "The upper part is milk, and the lower part is menstruation." There is also a record in Buddhist scriptures that "milk is transformed into blood."

【Truth】Breast milk is not transformed from blood!

The blood cells in the blood are large molecules, and they cannot enter the mammary glands through the capillaries in the human body. In fact, almost all the substances in breast milk are synthesized and secreted by mammary gland cells, and are not "transformed" from blood.

It is understandable that ancient people in China and abroad, due to their lack of knowledge of human physiology and anatomy, assumed that breast milk was transformed from blood when they observed that women stopped menstruating during lactation.

However, whether a woman will stop menstruating during lactation depends on her physiological condition and the secretion of hormones in her body. Not all women will stop menstruating during lactation.

[Relationship between blood and breast]

Blood is the fluid that flows through the heart and blood vessels in the circulatory system. The most basic function of blood is to transport oxygen and nutrients to tissues in various parts of the body and carry away metabolic waste.

Milk is secreted by the mammary glands of the breasts, which develop rapidly during pregnancy due to the stimulation of estrogen and progesterone. From the late pregnancy to the lactation period, under the influence of prolactin secreted by the pituitary gland, breast cells will synthesize various proteins and nutrients in breast milk and secrete milk.

The relationship between blood, mammary glands and milk

The mammary gland is equivalent to a milk factory, and the blood is equivalent to logistics. Moreover, this logistics company is not doing well and cannot even enter the gate of the food manufacturing factory, so it can only deliver the goods to the factory door. The food factory's product milk is delivered by another logistics company - Milk Duct.

Now we know that blood only provides nutrients to the mammary glands, and other substances in the blood cannot enter the mammary glands during normal physiological processes. Milk is synthesized and secreted by mammary gland cells.