Researchers often delve into the obvious and sometimes find surprising results. That s not true in the case of a report in the bulletin from the World Health Organization. Although it seems fairly obvious that as calories become more available, people would have the opportunity to consume more and maybe too much. Similarly, it s a no-brainer to understand that such over consumption could lead to overweight and obesity.
Dr. Stefanie Vandevijvere from the University of Auckland, New Zealand and colleagues from that institution and the NIH in the United States, examined data from 24 high-, 27 middle-, and 18 low-income countries. They used information on food availability and on changes in average body weights from data points that were at least 4 years apart. Using equations from the Institute of Medicine, they then estimated how many calories different populations need to maintain weight, and then the change in energy intake that could account for the increased average body weights that they found.
The major finding of the study was that there was indeed a significant association between changes in food energy supplies and changes in body weight the association was highly statistically significant in both directions. That is, as food availability increased so did average body weight, and as availability decreased, so did average body weight (this was observed in 5 countries).
In their discussion, the authors concluded For most of the countries included in this study, the change in per capita food energy supply was greater than the change in food energy intake theoretically required to explain the observed change in average body weight. They also advised that policies should be put in place to focus on getting populations to reduce energy intake by improving the healthiness of food systems and environments.
Dr. Ruth Kava, Senior Nutrition Fellow at the American Council on Science and Health, said The results of this study are not at all surprising we already know from other nutrition research that people will often consume more food when it is easily available. One must also remember that a significant association between A and B, does not mean that A necessarily causes B, or vice versa. It s not clear to me if this study really breaks any new ground, nor precisely how improving the healthiness of food systems and environments would be accomplished.