|MadSci Network: General Biology|
The protruding stomachs typically result from one of three factors.
The first is edema in the abdominal area [Moderator's note: edema represents a "puffiness" due to accumulation of fluid that has seeped from the bloodstream into surrounding tissues]. This edema is a result of a lack of proteins in the bloodstream. The proteins in the bloodstream cause water to remain in the bloodstream. As the concentration of proteins in the bloodstream decreases, the water moves out of the bloodstream and into the extracellular spaces. This causes edema. The edema is particularly evident in the abdomen--especially in children.
The second cuase of a protruding stomach is an enlarged liver which is a result of inflammation as well as an accumulation of fat. Fat accumulates in the liver because` there are not enough proteins to allow it to be transported in the bloodstream.
The third cause of the protruding stomach can be due to parasitic infections, which are very common in malnourished people and, of course, make their malnutrition worse.
The reference for this answer was "Understanding Nutrition, eighth edition" by EN Whitney and SR Rolfes.
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