Not claiming to be an expert on Angus, but wiki says he lived on “tea, coffee, soda water, and vitamins”. No protein/amino acids in most vitamins, although maybe they said vitamins when they meant supplements.

The obese starvation victim was mentioned in a scientific study I read. It’s entirely possible there was a link to another paper with more details but I didn’t follow it. I just recall reading that drove home for me the importance of protein while dieting.