Apparently, Cartesian reductionist "science" doesn't work any better for nutrition than it does for medicine. BIG surprise ?? =;-)
In any instance where there is life force (Vital Force :-) ... the Whole is always Greater than the sum of all the Parts.
People can do fairly well on an extremely broad range of foods -- people who are burdened by a lot of toxicity often develop food allergies.. as homeopaths we are naturally interested in our clients' diets, and should have a decent working knowledge of nutrition and allergens, and in which dis-ease syndromes the allergens may present a maintaining cause or barrier to cure.
Additionally, Mr. Pollan touched on points such as the environmental degradation persuant to factory farming .. he mentioned specifically rBGH .. but that is only one of hundreds or thousands of ill effects; including thousands of tons of antibiotics and other drugs (many now detectable in the Ocean, far away from land !)
Just as "modern medicine" is a misguided "non-cure" which is often far worse than the original dis-ease, so is factory farming wreaking havoc on health .. not only our human health, but the environmental health of the entire planetary ecology.
Mr. Pollan advocates what sounds a bit like a Reagonomics approach -- employees pressuring employers for "real" food as opposed to factory processed / factory farmed (please don't let it be also genetically mangled FrankenFood!)
Many individuals have the opportunity to take matters into their own hands, just by purchasing locally grown ORGANIC foods - personally I believe that "grass fed beef" is likely nutritionally superior, and in some senses ethically superior, but in the final analysis, the total resource cost of many animal proteins is fantastically higher than that of vegetable proteins .. and in a world where human starvation is very much a reality, it seems a bit careless to feed oneself largely at the top of such costly food-chains (which also are inherently producers of greenhouse gas, and possible toxicity into water runoff / water table.)