Here are some useful images that help to explain why North Americans have been getting heavier over the last few decades:
Over the past few decades, portion sizes of everything from muffins to sandwiches have grown considerably. Unfortunately, America’s waistbands have reacted accordingly. In the 1970s, around 47 percent of Americans were overweight or obese; now 66 percent of us are. In addition, the number of just obese people has doubled, from 15 percent of our population to 30 percent.
While increased sizes haven’t been the sole contributor to our obesity epidemic, large quantities of cheap food have distorted our perceptions of what a typical meal is supposed to look like. These portion comparisons, adapted from the National Heart, Lung, and Blood Institute’s (NHLBI) Portion Distortion Quiz, give a visual representation of what sizes used to be compared to what they are today.
H/T to John Scalzi for the link.