While calorie counts have been on the downswing, calorie intake is still far above where it once stood. Americans' daily average caloric intake is over 500 calories higher than it was in 1970, when the average hovered around 2,169 calories per day.
What does a more than 20 percent increase in caloric intake mean for the average American? Consider that a pound a fat contains 3,500 calories. Assuming that even a quarter of those calories represent excess energy beyond what's needed for daily maintenance levels, that translates into a pound of stored fat gained every month, or 12 additional pounds per year.
Portion sizes have seen a similar increase over time.
According to the U.S. Department of Health & Human Services
, in the last two decades alone, food portions in American restaurants have doubled or in some cases tripled. Portion sizes began increasing in the 1970s and rose sharply in the 1980s.
Many food portions greatly exceed USDA and FDA standard servings,
according to a study published in the American Journal of Public Health
. "The largest excess over USDA standards (700 percent) occurred in the cookie category, but cooked pasta, muffins, steaks and bagels exceeded USDA standards by 480 percent, 333 percent, 224 percent and 195 percent, respectively," the study found.
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