Originally Posted by
gitarzan
I don't have a hour and a half. Please have an executive summary on my desk by morning.
http://www.metafilter.com/85684/Sugar-The-Bitter-Truth
Sugar: The Bitter Truth.Robert H. Lustig, Professor of Pediatrics at UCSF, discusses the biochemical properties of fructose and makes the case for why it should be considered, essentially, a poison. [Youtube, 1.5 hours]
While the cane sugar vs high-fructose corn syrup issue is frequently discussed online, the two substances are remarkably similar. Sucrose almost immediately breaks into fructose and glucose (in 50:50 ratio) in digestion, while HFCS contains both in a 55:45 ratio. In Dr. Lustig's view, refined sugar and HFCS can be considered equally bad for humans, due to their fructose content.
His talk is focused on fructose, and goes into detail on the metabolism of it in the liver (since, unlike glucose, fructose can't be used directly by the other parts of the body). He also touches on USDA dietary recommendations, including the recent decades preoccupied with reducing dietary fat, as well as the commonly cited (kcal in - kcal out = weight change) equation and its shortcomings for addressing obesity
I.e. calories don't tell the whole story; fructose has an especially bad effect on the body because of its very different metabolic path.