[differentView]

>As an easy example, there are many that are more overweight than I am that know nutrition better than I do. That said, it is does seem somewhat logical to question health advice from clearly unhealthy people.

Using your easy example with OP's logic, a 100-pound overweight person trying to lose 100 pounds by throwing up and taking dangerous diet pills should also discount the advice of a physician who've never lost 100 pounds themselves or successfully helped a patient lose at least 100 pounds.

[taeric]

Hmm... if that is what the OP intended, yes. Mayhap I was giving too much charity, but I would take it more of "Where is the evidence that you have successfully helped a patient lose 100 pounds?"

That is, again, it is not bullet proof. But, it is too often for someone to have experience that does not scale to the speed and size of facebook in this regard. Life is too easy to argue in the extremes of straw men. Wanting to know of experience that backs an argument is perfectly reasonable.