Look at this great short video from Dr. Mark Hyman below, on why you should never eat high fructose corn syrup. Studies are looking into sugar in both a positive and negative light these days, but there is no telling yet, which dietary choice is better for everyone across the board.
But we do know that studies on manufactured man made sugars and sugar substitutes are really unstable and humans should stay away from them until we know more about them.
If you have sugar in your diet, make it a real source of sugar from cane, honey, maple, or fructose from fruit. Many of those have benefits if taken in moderation.