YES! And it's also a very addicting DRUG!
Take a look at the definitions. A toxin is a chemical produced by
living organisms that causes harmful effects on the body at high
enough concentration. Sugar easily meets that definition. It is plant
derived and there are numerous studies that show a variety of harmful
health effects from excess dietary sugar.
OK, is sugar a drug? If you've ever had a feel-good high immediately
after eating sweet "comfort" foods, it's a psycho-active drug. If
you've ever had a "craving" for something sweet, it's an addicting
So, my point is that we need to start thinking of refined sugar as a
toxin and drug. That makes sugar by far the most common and abundant
toxin and drug in the modern food world!