carorees wrote: That made me think...how can the health profession endorse a very low calorie diet of 800 cals a day or less for several weeks for the morbidly obese (which is probably less than 25% of their TDEE) and yet not endorse 25% of TDEE twice a week?!
Maybe things are different where I live, but here "the health profession" would not endorse such a severe calorie restriction. The advice here is slow sustainable weight loss, and most importantly, a change in life style, not a short term diet. This includes education about dietary composition, reducing sugar, simple carbs and processed foods (but not to the point of being fundamentalist); increasing physical activity through exercise and daily activities. Many programs also focus on emotional aspects of food, stress management, etc.
I agree, on one hand it sounds illogical not to endorse a calorie restriction. But on the surface, 5:2 sounds like a fad, so unless you have read up on it it is the calorie restriction and just that which would seem to be responsible for the weight loss.
I would imagine professionals who only know about the calorie restriction would worry about the obese person not learning about the above-mentioned aspects of weight loss. Just reducing calories and still overeating sugar, saturated fat, etc. may still have health risks. One may wonder how many will actually be able to do this for life. That being said, most diets, also those endorsed by the health authorities, fail in the long run for the vast majority of dieters, so we don't seem to really know what is working long term.
I'm still intrigued by the effect this diet is having on the amount of food I'm eating - I used to eat big portions of healthy food (i.e. high in fiber, low in simple carbs), but really big portions. I feel fuller much faster now, and I am much more aware of my body's signals. Also, I find 5:2 easier (and therefore hopefully sustainable) because my will power isn't challenged every day. That (and a bit of reading) was what made me try this despite the "fad alert signals". These aspects don't seem to be discussed by journalists or health professionals (who often just get a microphone stuck under their nose for a fast reply). So get those testimonials out there

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