So, how do you really avoid it, if you should really avoid it? Remember that sugar is a source of energy for our body cells. So, they are not bad unless you are diabetic. If you're not diabetic, don't abuse your pancreas and liver. They just might not be able to cope with high glucose in your blood. So, make sure your liver and pancreas are doing well.
Regarding the video above, treat it like added information. The thing is, yes, fruits have sugar, but at least, their sugar is natural. And, fruits are good for the body. :)