Diets-- wait let me rephrase that – lifestyle changes of eating fewer calories than one needs to maintain weight, and exercising to increase one’s fitness and burn calories, don’t “fail.” That is, they don’t fail on their own. They fail, if they do, because of several external reasons that many have posted, plus one reason that hasn’t been posted: one’s emotional / psychological issues surrounding food and weight/body image.
It’s very easy to sabotage oneself when attempting a significant lifestyle change, if you are unaware of the reasons for being overweight in the first place, and I mean the real reasons, not just the “he eats 'cause junk food tastes good and he has no will power” or “she eats 'cause she’s just a lazy fat pig” reasons. I’m sure a few people fit those descriptions, but I really don’t think it’s the majority.
Some people – and I think healthy, love-to-exercise types don’t necessarily know this (though some do) – are afraid to lose weight. The weight might be performing some emotional / psychological function; maybe it keeps them from doing things they fear, maybe it ‘allows’ them to remain unapproachable. It can be a shield or a wall. There are many downsides to being fat and I’m sure everyone on the SDMB can enumerate them. But there are benefits too, even though they seem incomprehensible and counterproductive to people who think being overweight is simply a despicable lack of will power.
I’ll stop speaking generally and speak specifically. I’m overweight. I have lost weight many times and know it can be done. I’ve regained the weight just as many times.
It’s significant that at none of these times, during the lifestyle changes I attempted and succeeded at for several months, was I concurrently seeing a therapist to deal with the issues that my decreasing weight was bringing up for me. And I don’t think it’s a coincidence that I continually sabotaged myself whenever I reached the point where I started getting more notice from men (yes, I said “more” – even at my heaviest, for whatever reason, I was still getting asked for my phone number; I remember thinking in exasperation, “How fucking fat do I have to get before they leave me alone? Am I some kind of magnet for every chubby chaser in NYC?”).
After finally seeking some therapy I realized that this mental exasperation shows exactly what I use my weight for, and why I get uncomfortable when my body approaches the thin side of the spectrum. For some reason I still haven’t figured out, I feel incredibly vulnerable as a thinner person. It’s like I’d have no right to say “no” to anyone or anything. My weight shelters me from attention I don’t want, or dont’ think I can handle. Of course it certainly doesn’t shelter me from negative attention; nor does it shelter me from the pain of not doing things I want to do because of shame. The thing I loved most in my life, performing, was no longer accessible to me. My weight took me out of the running for that. And maybe that was another thing I was letting my weight take care of: fear of failure, of competition.
All in all, I’d say my weight has a lot of pressure on it. Look at how much I’m relying on it just because I’m neurotic and scared! If my weight could talk it would probably say “stop fucking making me do all this! If you don’t want to do something, just don’t do it, don’t blame me for it.”
My current shrink and I are working on these issues, and doing so at the same time as dealing with the eating for all sorts of emotional reasons; eating instead of expressing anger, eating instead of feeling lonely, you name it.
Anyway, sorry to get all bloggy here. All this is not to say that the people the OP is kvetching about aren’t exactly wrong. And the OP isn’t wrong either. Of course taking in fewer calories than one requires will result in lost weight, even if it’s at a slower rate than the dieter would prefer. It’s not impossible. (I think the OP and many others who express this similar frustration are taking “it’s impossible” literally, when most people using it are being hyperbolic.)
But if you continually find yourself dieting and stopping before you reach your goal, or dieting and regaining your weight, it’s not the diet’s fault, and honestly it’s not the fat person’s fault either. It’s quite likely unconscious, or subconscious, self-sabotage, and (assuming one wants to lose the weight) one needs to find out why.
For the lucky folks who just ate a bit too much in college and gained the typical Freshman Twenty or maybe now live more sedentary lives in an office, there may be no psychological component, and more power to ya if you don’t have to address anything else but your excercise and eating habits. But please believe me when I say that for some of us, diet and excercise alone really won’t work in the long run, if we don’t address what this weight is doing for us. Because there clearly is a benefit, maybe more than one, and until that is addressed, until both the body and the mind get workouts, the yo-yo cycle will continue.