Blood

"Blood is a constantly circulating fluid providing the body with nutrition, oxygen, and waste removal. Blood is mostly liquid, with numerous cells and proteins suspended in it, making blood ""thicker"" than pure water. The average person has about 5 liters (more than a gallon) of blood.
A liquid called plasma makes up about half of the content of blood. Plasma contains proteins that help blood to clot, transport substances through the blood, and perform other functions. Blood plasma also contains glucose and other dissolved nutrients.
About half of blood volume is composed of blood cells:
• Red blood cells, which carry oxygen to the tissues.
• White blood cells, which fight infections.
• Platelets, smaller cells that help blood to clot.
Blood is conducted through blood vessels (arteries and veins). Blood is prevented from clotting in the blood vessels by their smoothness, and the finely tuned balance of clotting factors."

Hypoproteinemia

Hypoproteinemia (or hypoproteinaemia) is a condition where there is an abnormally low level of protein in the blood. There are several causes and all result in edema once serum protein levels fall below a certain threshold. This can be caused by several gastrointestinal conditions, including impaired pancreatic function, bacterial overgrowth in the small intestine, gastrointestinal infection, parasite infestations, diarrhea, Crohn's disease, or ulcerative colitis. In addition, individuals who have had part of the intestine removed surgically may experience hypoproteinemia.