I'm sort of surprised you haven't heard of this and it is being sung about on Reddit.

Dietary science is a mess but I would definitely say that the evidence currently favors something like the ketogenic diet (which closely resembles Paleo and past-decade trends like Atkins and South Beach.) Part of the problem is that this squarely contradicts what the medical community has advised for the past fifty years (eat more carbs, less fat!). It is difficult to overcome a) the education of older medical professionals and b) what people have been told in school and on the back of cereal boxes for decades.

There also definitely isn't enough data, especially on humans (or anything that isn't a very cancer prone rat).

Gary Taube's Good Calories, Bad Calories and Why We Get Fat are other standard references.