Let’s say, whilst wandering through a desolate wasteland, I become lost and malnourished. Fortunately I stumble upon some friendly types, who offer me a delicious selection of cooked meats in equal portions to sate my voracious hunger. Beef, pork, chicken, lamb, venison, fish and…the other white meat, long pig - human flesh. I’m only allowed to eat one. Putting morals and ethics aside for a moment, would there be any benefit at all in choosing people meat?
Probably not. In theory, it contains everthing your body needs, but other choices might offer you more opportunity to top up specific nutritional needs more effectively.
Fish (depending on the variety) could offer you some useful minerals such as iodine and zinc, Vitamins A and D, and Omega 3 oils
Pork might be a more calorie-dense choice because of the fat content (depends; is this lean or obese human?) - which could be a deciding factor if this is a one-off meal and you don’t know where the next one is coming from (maybe you are the next one, in which case, the nutrition question is moot)
Nice username/post combo there, Mangetout. 
Well, there’s always the possibility of contracting kuru, which sounds more fun than a barrelfull of monkeys. But next to other pathogens found in the other critters, if they’re undercooked, you’re probably pretty safe.