There's a syndicated sex advice columnist named Dan Savage who I know via his weekly column through The Onion's AV Club. He is known for talking in a straightforward manner and dealing frankly and often open-mindedly with sexuality in most of its forms.
Mr. Savage's advice often comes across as humorous and brutally honest. He'll call people "assholes" if he thinks they're jerks. He doesn't pull any punches and much of his advice is pretty spot-on. Sometimes though, his advice reveals his egocentric views and the limits of his experience. In essence, his thought processes operate as many people's do in that he believes that what he thinks, feels, and believes based on what he knows, has learned, and values is usually (if not always) correct.
Quite some time ago, there was a letter written by a woman to his "Savage Love" column and she said she was overweight, hairy, and lonely. She asked how she could find someone given her situation. Dan Savage's response was to go to the gym, lose weight, and undergo some sort of hair removal. As a man, and a gay one who has little experience in the physical health issues of women, he missed something that one of his readers caught the following week. A woman wrote in and said that the woman's description of herself had all of the symptoms of PCOS (Polycystic Ovary Syndrome) and that his advice may not help her since women who suffer from it have specialized needs in regards to weight loss and hirsutism.
This woman had problems which Mr. Savage didn't have the correct solution for because he didn't have the perspective or experience to recognize that she was not like him. For him, the answer to weight problems and hairiness were exercise, diet, and electrolysis. For her, they were likely medical treatment for a disease she didn't know she had.
I mention this case not because I wish to criticize Dan Savage. In fact, I liked the fact that he was willing to print the other woman's letter to help his reader in a way he may have failed to do so. I'm talking about it because there is often a myopia about how to lose weight when people dish out their advice. That myopia is induced by the glasses we each wear as a result of our own personal experiences and biased viewpoints. This topic came to mind after I followed a link on another person's blog to another blog in which a post appeared which asserted that there were some foods no one should ever eat until they'd lost all the weight they had to lose.
For some people, it is important to stay away from all of a certain category of food entirely if they want to lose weight. These people are addicts who can't trust themselves or condition themselves to eat in moderation. For others, the very act of that sort of rigidity induces despair at the possibility of long-term deprivation and makes it impossible for them to stick with a diet (and I use that word to mean "the food you eat", not a reducing plan) which is conducive to weight loss. To assert, unconditionally, that one has to do X, Y, or Z in order to lose weight is extremely self-centered and egocentric. It is essentially saying that there is one way to accomplish this task, and it is the way that works for you. Any other way is the road to failure.
I have issues with this sort of rigidity not because I care about all of the narcissism and steel-trap-closed minds in the world, but because the message being spread that there is naught but one road to success is a highly destructive one. If you spread the notion that you can't have a slice of pizza or a piece of chocolate until you have transformed into Slim Goodbody, then there will be a certain portion of the overweight population who will never even try because such rigid plans will not work for them. It wouldn't work for me, and I can say after 15 months in which my plan (which includes daily chocolate and often a salted snack in a small portion) has been working wonderfully for me.
In essence, the people who believe they know what is "right" based on what works for them are putting out a message that increases the chances of failure and a sense of futility when they offer such absolutism. They don't know every other person's issues (just as Dan Savage didn't know about PCOS), be they psychological or biological, yet they speak in absolute terms as if they know the one true path. I don't ask that people not feel that their way is right for them, but only that they at least crack their minds open enough to accept that it may not be the only "right" way for everyone rather than talk about what people should and shouldn't do to lose weight.