Whether you believe the conspiracies on that or not, there is some truth to it to an extent, which is why fruits in more exotic places often taste better as are more likely to be picked from a field which just grows naturally. However, the benefits of fruit far outweigh processed and refined sugars. Furthermore, the vitamins and fibre content are also of great help.
Fructose is a monosaccharide, meaning it is a single sugar molecule. sucrose is disachharide which s glucose linked ith fructose. Fructose is absorbed more slowly because of the presence of fiber and other phytonutrients in fruit and has a smaller insulin trigger sometimes may not ever stimulate an insulin secretion. Whereas sucrose whilst similar in makeup behaves differently (and generally heavily processed). Sucrose being a disachharide breaks into glucose plus fructose and are absorbed as 2 different elements. sucrose also creates insulin stimulation to help glucose transport into your tissues. this is the major difference between sucrose and fructose, it is hte presence of glucose.
However!!!
Fructose and glucose will be converted to energy, this energy is stored in a molecule called ATP. But, if your ATP levels are already high, instead of it being used for energy, the fructose and glucose change into fatty acids (triglycerides) for tissue storage (generally fat)
So since excess calories from glucose and fructose are used for the production of triglycerides, and these triglycerides are moved around the body in your bloodstream with lipoproteins.
These lipoproteins deliver these triglycerides all around the body. So...., extra calories from sucrose (and corn syrup (fructose based sugar)) rich foods can increase the amount of fat in your blood, thefefore liver, as well as muscles and generally fatty tissues.
However, the above is amplified greatly by processed and refined sugars, and less prominent with fruits owing to the make up of the fruit. So eat fruit will not be the same as eating a chocolate bar, not in any similarity.
Put it this way, if you like all those sweet fatty sugary foods they increases your risk for developing diabetes and heart disease. If that doesn't help you minimise your want for them then I don't know what does?!
If you like those foods, don’t eat them in excess, treat them as a treat!