In a report comparing food consumption patterns* in 1977-78 versus 2005-2008, Biing-Hwan Lin and Joanne Guthrie from USDA’s Economic Research Service found that on average, Americans consumed 75.2g of fat in 2005-08 compared with 85.6g in 1977-78.
Meanwhile, the percentage of total calories derived from fat also declined substantially from 39.7% to 33.4% between 1977 and 2008, said the authors.
“Mean daily consumption of total fat declined significantly over the period studied in both absolute terms (grams) and as a share of calories.”
Almost a third of calories now consumed outside the home
However, with more Americans eating out than ever before, a growing proportion of the fat that they do consume is the unhealthy, saturated, variety, said the authors, noting that almost a third (31.6%) of calories were from foods consumed outside the home in 2005-8 compared with just 17.7% in the late 1970s.
“Food consumed away from home is higher in saturated fat than foods consumed at home [in the 2005-8 data set].
“The higher percent of calories from saturated fat in fast-foods was especially noteworthy at 13.5%, compared with 11.9% in restaurant foods, 12.3% in school foods, and 10.7% in foods consumed at home.”
Similarly, foods consumed away from home in 2005-8 contained significantly more sodium (1,820mg of sodium per 1,000 calories), than foods consumed at home (1,369mg sodium per 1,000 calories); with foods from restaurants and fast-food outlets particularly sodium-dense at 2,151mg and 1,864mg of sodium per 1,000 calories, respectively.
Calcium intakes have gone up
On a more positive note, mean daily calcium intake rose from 743mg in 1977-78 to 919mg in 2005-08.
However, much of this is coming from foods eaten at home, said the authors. “For every 1,000 calories from foods consumed at home, Americans increased their calcium intake from 425mg to 559mg in that time period, whereas the calcium density in foods consumed away from home remained relatively constant at 452-460mg per 1,000 calories.”
Meanwhile, the amount of calcium per 1,000 calories from school foods declined from 742mg in 1977-78 to 646mg in 2005-08, while the amount of calcium per 1,000 calories in fast-foods increased from 344mg in 1977-78 to372 mg in 2005-08, they added.
“Even though school foods had the highest calcium content among all food sources, low calcium content in foods consumed at restaurants and fast-food places resulted in lower calcium content overall for foods consumed away from home at 460mg per 1,000 calories, compared with 559mg for foods consumed at home.”
Dietary fiber per 1,000 calories is lower in foods consumed away from home
Finally, foods consumed away from home, especially fast-foods, were lower in dietary fiber than foods eaten at home in the 2005-8 data, at 6.8g fiber per 1,000 calories versus 7.7g fiber per 1,000 calories.
*The report analyzed national food consumption survey data from the 1977-78 Nationwide Food Consumption Survey conducted by USDA plus data from the 2005-06 and 2007-08 National Health and Nutrition Examination Survey (NHANES), which is conducted jointly by USDA and the U.S. Department of Health and Human Services.