Kieran you know when you should quickly stop reading a webpage?......... When it has links for 'Curry to combat cancer' and 'Cabbage Soup Diet'. Also when the word calories is used and the title of the site has the words 'Weight loss' in it.
'Weight' means absolutely nothing unless you compete in a weight category. Body composition on the other hand should matter to everyone. Forget the BMI and all that junk, look in the mirror:
- are you fat? Then your malnourished
- Are you a lean, mean, strong machine? Congratulations you're nourished.
P.S. Crossfit has infinite examples of real science (e.g. the zone, paleo, oly lifting, starting strength, mma) applied in the real world (e.g. people not lab rats where every other varible is taken out of the equation)