“To really know what a person is eating you’d have to have a second invisible person following them around, taking photographs, looking at ingredients, and consulting accurate food composition tables, which we don’t have.” When you report on an FFQ that you ate a carrot, the tabulator consults a U.S. Department of Agriculture database to determine exactly how much calcium or beta-carotene that carrot contained. But because all carrots are not created equal, their nutrient content varying with everything from the variety planted and type of soil it was planted in to the agriculture system used
...more
