Gary Taubes is a fine evangelist against obesity and fatness, but sugar is not toxic: The case against sugar - A potent toxin that alters hormones and metabolism, sugar sets the stage for epidemic levels of obesity and diabetes.
Sugared foods are delicious treats. Cheap and abundant carbs (converted to sugars during digestion) are a blessing for mankind. Historically, only the rich and royalty could be fat. Now, the poor are wealthy enough to get fat while it is the prosperous who tend to be physically fit and trim. The social part has flipped: plebians are fatter, patricians trimmer. It is sociologically interesting.
It is also medically interesting that carbs, including sugars, alter your insulin metabolism. Of course they do, but these issues are only of academic interest unless you have a desire to lose fat.