Robert Lustig lecture videos are a good place to start. Anything 60 or 90 minutes will not waste your time. (I run them with captions at 1.5x-2x speed, so 30-60 minutes.) His books have complete references.
Robert Lustig is the very best kind of scientist: he never claims anything without a dozen peer-reviewed double-blind controlled trials to back him up, many of which he supervised personally.
To be an endocrinologist, you have to be twice as smart and careful as any other sort of medical doctor just to be able to do your work. Another is Robert Sapolsky, who also writes exhaustively supported books. Anybody who says they understand some metabolic process and is not an endocrinologist with 30+ years work behind them is a liar.
