I didn't Google it because I was there and lived it.
Coke stopped making Coke in 1985, and made New Coke. New Coke sucked, but it was designed to suck. They stopped making Coke so they could switch it from sugar to HFCS, to save production cost and appease Big Corn. A few months after New Coke came out, Coke Classic was re-released, and the people rejoiced.
And obesity rates began climbing at that very moment. NOT just from Coke having switched from sugar to HFCS, but from the entire food industry taking Coke's lead.
True, all sugar can make you fat, because sugar is caloric, and calories add up. HFCS, however, is something else entirely. Besided being hyper-sweeeeet and making you eat and drink even more HFCS, I'm pretty sure it's metabolized in your body differently that sugar.
Fact is, the nation began getting fatter when Coke Classic came out.