Gut: The Inside Story of Our Body's Most Under-Rated Organ

by Giulia Enders

Unlike other nutrients, it cannot be absorbed straight into the blood from the gut. Fat is not soluble in water — it would immediately clog the tiny blood capillaries in the villi of the gut, and float on top of the blood in larger vessels, like the oil on spaghetti water. So fat must be absorbed via a different route: the lymphatic system. Lymphatic vessels are to blood vessels as Robin is to Batman. Every blood vessel inside the body is accompanied by a lymphatic vessel — even each tiny capillary in the small intestine. While our blood vessels are thick and red, and heroically pump nutrients to our tissues, the lymphatic vessels are thin and transparent-whitish in colour. They drain away fluid that is pumped out of our tissue, and transport the immune cells which ensure that everything is as it should be throughout the body.