In the book, In Defense of Food, Michael Pollan says that we need to eat food. However, he isn't simply referring to the t.v. dinners and candy bars I love to eat, but real food, the kind our grandparents used to eat. He refers to the trend of "nutritionism", which is (in short) the practice of food fad-ism. Food is reduced to nothing more than nutrients, and scientists are working hard to find ways to eliminate the unpopular nutrients and incorporate the "good" ones into the genetically engineered stuff we eat today. Under the guise of nutritionism, anything can claim health benefits, even candy bars! But instead of becoming healthier, this Western diet is giving us heart disease, diabetes, obesity, and other kinds of "unsavory" diseases.
One point I'd like to refute is that humans need mostly plants. Although it is suspected by many that a diet consisting mostly of plants is the most beneficial, Pollan himself says later in the book that it doesn't matter what kind of food you eat, as long as it's real. Humans are adapted to a large variety of foods and can thrive on bugs, meat, dairy and other such diets. He even suggests that the health dangers associated with such foods may not be what is naturally in the food, but rather what we humans add to it (ie: antibiotics, growth hormones, etc.), and the way that we make it (ie:feeding cows corn instead of letting them graze naturally).
I do agree that food can not be re-created in a laboratory. A book I am reading, called Greater Healh God's Way, makes much the same point, and it was written in 1984! People have long suspected that our current scientific knowledge cannot measure up to what nature has evolved to give us (or God).
The link I included above takes you to Stormie O'Martian's testimonial, and a summary of her book. I included it because I think Michael Pollan and Stormie O'Martian would agree in their nutritional beliefs.