Short version:
-Glucose = good, natural, healthy sugar.
-Fructose (Ie High Fructose Corn Syrup) = less good sugar. 30% converted into fat. Contributes to a ton of health problems. Has effects on the body similar to alcohol. The difference is, Fructose is not processed in the brain, so its not "felt" like alcohol.
-A calorie is not just a calorie. A calorie of fructose has a drastically different effect on the body compared to a calorie of glucose. Good calories matter.
-The related health issues can all be very generally categorized under "metabolic syndrome"(wiki it), and America as well as the rest of the world is suffering from this epidemic.
-The long and short of Fructose's effects on appetite is that our bodies have a naturally functioning system that handles fullness. Enzymes and hormones work to tell the body "Okay you're full, stop being hungry." Fructose interferes with that, leading to people gorging like motherfuckers, feeling hungry when their bodies have sufficient nutrition. Insta-obesity.
-Fructose fucks up the liver over time simply by processing it. Processing too much and you're fucked.
-The normal, healthy range of calorie intake is something like 15g fructose, 30g total sugars per day. We're way up in the hundreds right now.
-Fructose is such a mainstay because of processed foods. Almost all processed foods have HFCS injected in it.
There's a lot more key points, but I cant think of em right now.