You lose that bet. It's just the same old keto-quackery you've read a thousand times before.

And by the way, he does admit it's all about calories in - calories out. From his book "excess calories may certainly be the proximate cause of weight gain, but not the ultimate cause". By which he means that it comes down to calories but keto automatically makes you eat fewer calories.

He also promotes this ridiculous theory that the US low-fat low-sugar dietary guidelines caused the obesity epidemic by promoting low fat even though fat consumption in the US has increased since then and the US has one of the highest fat consumption in the world. But hey, conspiracy theories sell.

He is a legit MD. He's also a zealot just trying to sell books.