Matters got even sketchier in the second half of the survey, when I was asked to specify how many times in the last three months I'd eaten a half-cup serving of broccoli, among a dizzying array of other fruits and vegetables I was asked to tally for the dietary quarter. I'm not sure Marcel Proust himself could recall his dietary intake over the last ninety days with the sort of precision demanded by the FFQ.

—Michael Pollan, In Defense of Food: an Eater's Manifesto