Table sugar (sucrose) consists of two bonded molecules: glucose and fructose. Inside the body, the bond is broken and glucose and fructose are released. The bloodstream picks up the glucose molecule and delivers it to any organ or muscle tissue that needs energy. The fructose molecule, however, can be metabolized only by the liver, which evolved to handle small amounts as early humans stumbled across the occasional stash of honey or bounty of seasonal fruit. These days the average daily fructose intake is 54.7 grams (nearly 14 teaspoons) — far more than the liver can metabolize.