We've blogged before about the obesity epidemic, and whether or not it is a recent phenomenon; John Komlos and Marek Brabec have argued that obesity rates actually began rising in the early 20th century. A new study (abstract; PDF) by Paul von Hippel and Ramzi Nahhas looks at 60 years of data on child obesity and finds that the increase in obesity rates started with children born in the 1970s and 1980s. Von Hippel wrote to us in an email:
Intrigued by the conflicting extrapolation results, Ramzi Nahhas and I decided to look at measurements that were actually taken before 1960. We analyzed the heights and weights of children in the Fels Longitudinal Study, an ongoing study that since the 1930s has measured children from shortly after birth until age 18. Most of the children come from the area near Dayton, Ohio, which is not a mirror of the nation but has an obesity rate that is close to the national average.