He is 75 years old with a much smaller appetite and metabolism, this would be much harder (if true) than if he was feeding the fiery hot furnace of an active 20-year-old.
I also think that almost any of us could eat vegan if we had a full-time top chef preparing all of our meals except for the ones that we eat at the top restaurants in Los Angeles.
Never drink liquids during meals. It dilutes your digestive juices. And for sure!!! Never ever drink iced liquids during meals. Iced tea etc. will give you incomplete digestion, thus more fats deposited in you. Allow an hour or two before drinking.
Exceptions are a hot soup during cold weather and black coffee after a fatty meal such as bacon and eggs, or a meaty dinner.