New federal data confirms dietary sodium intake stable
Americans' nutrient intakes have been tracked by the U.S. Department of Agriculture since the 1930s. New 2003-2004 data were released yesterday showing Americans' salt consumption remains stable. The National Health and Examination Survey (NHANES) data were analysed in a new report, What We Eat in America, NHANES, 2003-2004, showing that dietary sodium intakes averaged 3,408 mg/day.
Anti-salt alarmists often contend that Americans are eating 4,000 - 5,000 mg/day; some even as high as 7,000 mg/day.
The NHANES data require one explanatory note, however. They track only sodium naturally occurring in foods (estimated to be about 10% of the total) and that being added in non-home food preparation either in restaurants or in the preparation of commercial food products (estimated to be 75% - 80% of the total). About 10% - 15% is added in home cooking or at the table. So, it would seem reasonable to add 10 - 15% to that 3,408 for Americans' intakes. The background intake levels of persons enrolled in medical trials where sodium data is measured accurately actually produce lower values, however, so the "dietary recall" of NHANES subjects may not be exactly right. Even so, the data have been produced in a consistent stream since the early 1970s and represent a time series. Over time, the measurements have improved, resulting in somewhat higher numbers, but the gradual rise in sodium recorded in the NHANES data also reflect another dynamic, often overlooked.
At least since WW II, Americans have been eating more foods prepared outside the home and doing less home cooking. In 1972, for example, restaurant spending represented 26% of Americans' total food spending. By 2004, that had risen to 42%. "Round can" sales of table salt have steadily eroded as less is being added at home. Since the medical studies show consistent sodium intakes over the past century, the decline in round can sales offsets the rise in NHANES-collected data on sodium in processed foods. This amounts to less than a half percent per year, but over time it adds up.
And it conveys a picture that is easily demagogued by anti-salt activists who claim Americans are eating not only too much salt, but more salt than in the past. The NHANES data put the lie to that assertion.
