The versions corresponding to NHANES 2001-2002, 2003-2004, 2005-2006, 2007-2008, and 2009-201035-39 were used to code, process, and analyze dietary data for nutrient content. Almost 7,000 foods from all food groups, including their source (eg, from fresh, frozen, or canned) and method of preparation (eg, cooked or raw or with
added salt) were included. Each food is identified by a unique
eight-digit code