I feel like a lot of people are missing an important detail - what you eat can be a lot more important than how much you eat. The 'voracious hunger' that a fat person might feel after a small meal is most likely a side effect of the type of food that they normally eat. Foods are like drugs, you're ingesting chemicals that have specific effects on your body.
I challenge you to cut about 90% of the meat out of your diet, replace it with vegetables and whole grains, and eat as much as you can. You'll feel better and you'll still lose weight
That was my initial reaction. But at that level of responsibility I much prefer someone being appointed for their competency to manage well rather than their ability to do technical work. I have no idea if Chu is a good manager or not, just saying that the Peter Principle is something to be avoided.
The role of a professor in research at a university IS mostly management. Especially with a high profile scientist like Chu, much of his work would be traveling and raising grant money while giving suggestions and guidance to a large group of graduate students who do the actual lab work.
"Most of us, when all is said and done, like what we like and make up reasons for it afterwards." -- Soren F. Petersen