Dr Pontzer's book, Burn was published in early 2021.
Loved his book, so put his quote in my signature below.

"Without Being Miserable" is SATIETY.

While it sounds logical that fasting or eating 800 calories a day would lead to weight loss, fasting can drive people to push their bodies to unsustainable extremes.

-A lack of focus on good nutrition, particularly getting enough protein, can lead to a loss of precious lean mass.
-A loss of muscle from long-term calorie restriction can lead to a downregulation of your metabolic rate, meaning you’ll need to keep eating less and fasting for longer to keep the weight off.

Eventually, your body increases your appetite to get your attention to ensure you survive. Unfortunately, we tend to make less optimal food choices when hungry. Rather than prioritising protein and nutrients, we gravitate to foods with the magical hyperpalatable combination of fat and carbs that will refill our glucose and fat fuel tanks quickly without providing adequate protein and nutrients.

I posted a good interview with one of the other researchers in Herman Pontzer's lab at Duke just yesterday.

https://forum.lowcarber.org/showthr...865#post9468865