When the gut is exposed to higher concentrations of fructose, it bypasses gut metabolism and enters the portal system, preferentially reaching the liver.

“when you expose the gut to higher concentrations and presumably higher doses so there's really a dose concentration problem which we'll come back to it it basically manages to get through the gut without the gut doing the metabolism and then it's going to enter the portal system”

“and remember that the intestine does act as a shield for up to like five or four to six grams of fructose so if you eat four or five grams of fructose and a fruit the the intestine is going to protect you in addition the intest you have fiber in a natural fruit and that slows the absorption so the concentration of fructose that gets to the liver is lower so there's less ATP depletion”