You can read Gary Taubes stuff. He is a science writer, who was sucked into the diet controversies about 10 years ago. Books and articles in NY Times Magazine, among others. http://www.garytaubes.com/
Books:
Look for these articles in NYTimes Magazine:
There are online videos linked from his site.
This video is from an appearance in 2011 in
Walnut Creek:
http://www.youtube.com/playlist?p=PL4427DBF43190B080
(Search youtube for "Gary Taubes Walnut Creek")
For Sugar, there is also the Robert Lustig: "Sugar, the bitter truth" (search for it on Youtube -- 90 minutes.
A 90-minute discussion of the nuances of fructose biochemistry and human physiology. He does not like Coca-cola.
Lustig is a specialist on pediatric hormone disorders and the leading expert in childhood obesity at the University of California, San Francisco, School of Medicine
Warning: After viewing this, you probably won't be drinking gatorate, soda, or fruit juice.
Started as a cardiologist, and moved into dieting and nutrition when he found out about low carbohydrate diets (he was far from the first), and set up a clinic in NYC, along with a radio show in the 70s. He passed away some time ago, but his name lives on. I find his books "Atkins Diet Revolution", for one fairly interesting. Read Gary Taubes to find out why this is not in the mainstream.