In the 2009 book "Fat Chance," the author, Dr. Robert Lustig, claims that sugar stimulates the brain's reward system the same way that tobacco, alcohol, cocaine, and even heroin does, and therefore must be equally addictive. Lustig even cites studies that show parts of our brain that light-up from a sugary reward are the same parts that get excited for many types of enjoyable activities, from drinking alcohol to having sex.

The problem, however, with these types of scientific studies of the brain is that "In neuroimaging, there is no clear-cut sign of addiction," Hisham Ziaudden, an eating behavioral specialist, told Levinovitz.

So, scientists don't know what addiction in the brain looks like, yet, and until that mystery is solved we should not be living in fear from something as fanciful as sugar addiction.