Leesburg, Va.

IT’S 42 steps from my back door to the garden that keeps my family supplied nine months of the year with a modest cornucopia of lettuce, beets, spinach, beans, tomatoes, basil, corn, squash, brussels sprouts, the occasional celeriac and, once when I was feeling particularly energetic, a couple of small but undeniable artichokes. You’ll get no argument from me about the pleasures and advantages to the palate and the spirit of eating what’s local, fresh and in season.

But the local food movement now threatens to devolve into another one of those self-indulgent — and self-defeating — do-gooder dogmas. Arbitrary rules, without any real scientific basis, are repeated as gospel by “locavores,” celebrity chefs and mainstream environmental organizations. Words like “sustainability” and “food-miles” are thrown around without any clear understanding of the larger picture of energy and land use.

The result has been all kinds of absurdities. For instance, it is sinful in New York City to buy a tomato grown in a California field because of the energy spent to truck it across the country; it is virtuous to buy one grown in a lavishly heated greenhouse in, say, the Hudson Valley.

The statistics brandished by local-food advocates to support such doctrinaire assertions are always selective, usually misleading and often bogus. This is particularly the case with respect to the energy costs of transporting food. One popular and oft-repeated statistic is that it takes 36 (sometimes it’s 97) calories of fossil fuel energy to bring one calorie of iceberg lettuce from California to the East Coast. That’s an apples and oranges (or maybe apples and rocks) comparison to begin with, because you can’t eat petroleum or burn iceberg lettuce.