I didn’t claim you referenced all of YouTube… but you did reference the person who is probably the most popular fructose alarmist out there at this time. You can find a popular proponent of any position lecturing on the subject on YouTube.
Dr. Lustig does refer to the science, but his conclusions aren’t well-enough substantiated by the evidence he presents, and are contradicted by other evidence in the research. People better at this kind of analysis than you or I have picked through the details and drawn this conclusion.
@casssax’s post quotes one such researcher, Alan Aragon, but there are a great number of people in the field - including substantially all dieticians - who will agree whole-heartedly with the position Alan lays out in the quote Casssax provided, and will disagree with Lustig’s fixation on fructose as the main culprit.
In my opinion, after doing an awful lot of reading and research, most camps are excessively fixated on the problems caused by overeating their particular villain - whether it be fructose, or sugars generally, or cholesterol, or fats generally, or whatever - versus the fact that the overeating is the problem. The vast majority of the research shows that when we don’t overeat in the first place, the body does a really good job of staying healthy on a wide variety of sources in a wide variety of ranges.
Put simply: when you overeat, the things which have the biggest excess in your diet are likely to dictate the kinds of problems you develop. But if you don’t overeat, those same things are unlikely to cause any problems, as long as they’re within wide but reasonable levels.