"You must not eat meat that has its lifeblood still in it." (Genesis9:4)
So Jews never eat blood and never take it as food.
Why do Christians not consume blood?
There are two reasons.
One of them is based on the ancient Bible.
The scientists found that the blood is a source of germs and infections.
It circles the body all the time, so it has the potential to have germs and infections.
Another reason is that blood can distort the taste.
This is why you have to eat kosher.
As Christians, we eat kosher and keep healthy.
But foreigners have always had the habit of consuming blood, especially in the Chinese culture.
They have very few dietary restrictions.
In China, they enjoy eating blood products such as chicken blood and duck blood.
Local people in Canton are fond of consuming wild animals such as snakes.
The Chinese in Africa even eat crocodiles.