to be fair most doctors aren't fat.

most patients are though, regardless of what they're in for.

even mental health patients are fat ( the ones that aren't junkies or anorexics ).

obesity is basically an outward manifestation of ignorance, stupidity and poor impulse control which then has downstream effects like Diabetes and then further down Heart Disease and other conditions.

i will rephrase what you said in more general terms - NEVER TAKE ADVICE FROM A FAT PERSON. 

 unless his advice is " never allow yourself to get as fat as me,  you will regret it "

then take the advice !