This is an important point. Here’s my “pet” theory as to why some people like high P:E diets (protein to energy, advocated by Ted Naiman). If you’re not using a lot of energy, higher protein diets can make sense, and this is particularly true if you’re muscular. In the latter instance, I think the musculature help to blunt the insulin response (muscles act like an insulin sink) and therefore any increased hunger you might get due to increased protein would be less.
That’s why people like Dr. Naiman, who does very short intense body weight training (and is muscular) can handle high P:E.
I hypothesize that people who aren’t going to like high P:E will be those with high calorie requirements. If you’re Zach Bitter and running a marathon a day, you will NEED to eat more fat (or some carbs, which is what Mr. Bitter does). Even Shaun Baker, with the amount of lifting and aerobics he does, I doubt he could handle high P:E.
Between these two extremes, it becomes less clear, of course.
I also note it’s not easy to convert protein to energy. I know, everyone will be like, “But what about GNG??” While that’s a factor, I think that converting protein to energy is inefficient, at best.
Unfortunately, not a lot of studies in this area. This once comes close…but compares high protein/no carb with…normal protein/high carb (high for us). Would love to see the same study with high protein/low fat versus low protein/high fat, both zero carb.
Design: Ten healthy men with a mean (±SEM) body mass index (in kg/m2) of 23.0 ± 0.8 and age of 23 ± 1 y received an isoenergetic H diet (H condition; 30%, 0%, and 70% of energy from protein, carbohydrate, and fat, respectively) or a normal-protein diet (N condition; 12%, 55%, and 33% of energy from protein, carbohydrate, and fat, respectively) for 1.5 d according to a randomized crossover design, and EE was measured in a respiration chamber. Endogenous glucose production (EGP) and fractional gluconeogenesis were measured via infusion of [6,6-2H2]glucose and ingestion of 2H2O; absolute gluconeogenesis was calculated by multiplying fractional gluconeogenesis by EGP. Body glycogen stores were lowered at the start of the intervention with an exhaustive glycogen-lowering exercise test.