Part of the reason Americans have gotten so fat is that our jobs have grown more sedentary. In a review of energy expenditure in US private employment since 1960, scientists report that men are burning an average 140 fewer daily calories on the job; for women, its 124 fewer calories a day. The obesity epidemic has largely been blamed on overeating, but this research also implicates a switch from jobs in factories and farms to office work: In the early 1960s, 48% of the jobs in private industry required at least moderate physical activity, but today thats dropped to 20%. Researchers noted, This reduction in occupational energy expenditure accounts for a large portion of the observed increase in mean US weight over the last five decades. In a separate study, the CDC reported that only 6.5% of US adults currently get enough physical activity on the job alone to meet current guidelines.
TO LEARN MORE: PLoS One, dx.doi.org/10.1371/journal.pone.0019657.