Thanks for analysing the reductionist f & v research and eliciting the inevitable flaws.
Additionally we need to incorporate into these studies the food ratios carbs-proteins-fats %s. Obviously someone eating fruits and veges with too much overt oil (10% by calories as a benchmark)will negate the benefit of f& v compared to someone careful about this important parameter.
The researchers themselves have to have a comprehensive integrated understanding of nutrition in order to design a useful study... We have a long way to go....!

and please Ms Olivia do not resort to gene explanations as if genes are determinants - that is "post" reductionist and has led us to the present mis directed science both in medicine and agriculture...