There’s no shortage of speculation as to why 70% of us in the U.S. are overweight or obese. A few possibilities include:
- we’re too sedentary
- we eat too many carbohydrates
- we eat too much fat
- our foods are over-processed
- we eat away from home too often
- we eat too many industrial seed oils
- our water and food are contaminated with persistent organic pollutants that disrupt our endocrine systems
I was reading an article at Nutrition Today and came across this graph of calorie consumption change from 1971 to 2004 (or 2000?):
A verbal summary is from this article cited by the the Nutrition Today authors: “During 1971—2000, a statistically significant increase in average energy intake occurred. For men, average energy intake increased from 2,450 kcals to 2,618 kcals, and for women, from 1,542 kcals to 1,877 kcals.”
So men’s daily calorie intake went up by 168, and women’s by 335.
The original article I read states, alternatively, that men’s daily caloric consumption rose from 2450 to 2693, a gain of 243. I can’t explain the discrepancy between 243 and 168, nor why 2004 is in the graph instead of 2000.
Maybe you don’t think an extra 168 calories a day is much. If you believe in the validity of the Energy Balance Equation, those 168 daily calories will turn into 17.5 pounds of fat in a year unless you “burn them off” somehow. If you weigh 150 lb (68 kg), you can burn those 168 calories by doing a daily 15-minute jog at 5.5 mph (8.9 km/hr). But you ain’t gonna do that. (I’m not getting into a debate about validity of the equation now; for another perspective, read Lyle McDonald.)
But year 2000 was a long time ago. How much are Americans eating now? According to a 2016 report from Pew Research Center:
Broadly speaking, we eat a lot more than we used to: The average American consumed 2,481 calories a day in 2010, about 23% more than in 1970. That’s more than most adults need to maintain their current weight, according to the Mayo Clinic’s calorie calculator. (A 40-year-old man of average height and weight who’s moderately active, for instance, needs 2,400 calories; a 40-year-old woman with corresponding characteristics needs 1,850 calories.)
Bottom line? We’re eating more than we did in 1970. Which could explain why we’re fat. Unless we’re burning more calories than we did in 1970, which I doubt.
PS: In scientific literature, “kcal” is what everybody else calls a calorie.
PPS: Why we’re over-eating is a whole ‘nuther can o’ worms.