It seems that consensus that a low fat/high fruit and vegetable (LFFV diet) is the 'best' one. The UK government wanted us to eat 5 portions of fruit and vege a day, and now they are wanting us to eat even more. However in 2011, research confirmed that those who ate the most fruit and vege were no less likely to get cancer than those who ate the least, and the evidence for fruit and vege preventing heart disease was weak. Yet the government kept up with the 5 a day campaign.
The other argument against the LFFV diet is studies of supercenterians (people living to 110 years old, or older). Many have attritubed their longevity to olive oil (a fat), yet I am not aware of any who ate unually large quantities of fruit and vege. One lady in America used to live practically off chicken, crispy bacon and ice cream!
Finally my other argument is that I have noticed that people I know who eat lots of salads and fruits and probably consume less protein and fat than average, seem to look old for their years or they look pale and ill. Yes weight loss is an attactive reason to movitative people to do the LFFV diet, but how about people who can manage to control their weight without it?