I would just have to say that this is a ridiculous remark!
Being able to provide sound advice on dieting has mostly to do with what you have learned and read about the subject through the years. being able to execute them yourselves is a different story for many..
Would advice from a person as stated above be worth anything to many people?...maybe not... , but it is still undeservingly harsh to state such a remark.
There are many people out there giving advice on all sorts of topics they have not experienced first hand..
Your post was simply disgusting and rude for no reason..
that's all..