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Marion Nestle's hefty new book, What to Eat: An Aisle-by-Aisle Guide to Savvy Food Choices and Good Eating (North Point, $30), is on one level the successor to The Supermarket Epicure, Joanna Pruess's 1988 book about managing to eat well with foods bought at places like Safeway. This was tricky enough 20 years ago, and as Nestle demonstrates, it has become more so.
In the past two decades, food companies have become even bigger and their marketing tactics even more sophisticated, which means, more or less, that when you step into a supermarket today, you are like a lab rat entering a maze in some elaborate experiment. You must have your wits about you if you hope to negotiate the maze to your advantage, and while Nestle's book isn't exactly a pocket-size guide, it can profitably be examined beforehand, so when you finally do set off to do the food shopping, you will have a pretty good idea of what you can expect to find — in particular, how the marketing machine will attempt to manipulate you, and why.
In the largest sense, of course, the why isn't difficult, for it is the job of food companies and supermarkets to sell you as much or as many of their most lucrative products as they can, and their most lucrative products are likely to be full of inexpensive, highly processed ingredients (i.e., corn syrup), bundled up in gaudy packaging, and not especially good for you — surprise!
There isn't much revelation in How to Eat, but Nestle is an attractively peppery writer, and she brings a good deal of lore — about nutrition, marketing, agriculture, politics — to her scrutiny of a routine chore too many of us think too little about. She repeatedly makes a point, too, that's worth repeating: The true value of organic agriculture isn't that it might result, here and there, in slightly higher levels of certain nutrients or even that it definitely reduces the presence of pesticides and other chemical dangers in the food we eat. What really matters, she writes, is that organics represent "a political choice. When you choose organics, you are voting with your fork for a planet with fewer pesticides, richer soil, and cleaner water supplies ... for conservation of fuel resources and the economic viability of local communities, along with freshness and better taste." By Jove, I think the forks have it!