I would offer this as being pretty much a required book for anyone at all interested in the quality of the food that they are feeding themselves and their children.
Harvey's book is both well written and (it seems to me at least) very well researched. In essence, he offers evidence that modern industrial farming techniques are robbing foodstuffs of a high proportion of important nutrients - minerals, fatty acids and others. He links this in with the rise in rates of so-called diseases of affluence, which has been done to an extent by others, but goes further to suggest that illnesses such as dementia and behavioural difficulties may in no small way be linked to a deficient diet.
Harvey examines the ways in which nutritional balance could be returned to foods and how the production of even "organic" foods has been grossly compromised by the application of industrial farming techniques and a stretching of the definition of "organic."
Harvey provides plenty of reference to research in his text, but also includes considerable anecdotal evidence: if I have a criticism of the work it is that sometimes it is difficult to see where the hard science ends and the anecdote begins, but in general he does a good job in separating fact from speculation.
Highly recommended for anyone interested in farming, food production and, indeed, what they are putting into their mouths.