Fructose is processed in the liver. To greatly simplify the situation: When too much fructose enters the liver, the liver can’t process it all fast enough for the body to use as sugar. Instead, it starts making fats from the fructose and sending them off into the bloodstream as triglycerides .

Laura Dolson-Low Carb Diets Expert (See more on lowcarbdiets.about.com .)