I remember hearing this before – but apparently this is the first major American study of its kind:
“The Rising Cost of Low-Energy-Density Foods” (Monsivais and Drewnoski, 2007; J. Americ. Diet. Assoc. 107: 2071-2076; if your university has a subscription, you can access the full article here, and here’s the press release)
What constitutes a particular food’s Energy Density? Well, “Energy density, expressed as kcal/g or MJ/kg, is a measure of available energy per unit weight and can be used to describe individual foods, menus, or total diets…”
Why is this relevant? Again, from the paper: “In recent studies, diets of lower energy density were associated with higher dietary quality and with lower body mass index (calculated as kg/m2) values in adults. Lowering the energy density of the diet through consuming more vegetables and fruit is a recommended strategy for management of body weight.”
In short: cheetos, cheese smothered chili dogs, and entire sticks up butter aren’t good for you; vegetables and fiber are.
Really -I think we can all admit we already knew that. However…Apparently, healthier food items (in one Seattle market, mind you and only over a 2 year period) are both more expensive AND have risen in cost 20% more than their trans-fat filled ugly cousins:
*indicates a statistically significantly different result from the high energy group (5)
So, the poorer you are, the more likely you will have to resort to lower-quality foods to feed yourself. As the authors put, “…the present analysis is the first to provide vital evidence that it is the foods of lowest energy density (excluding beverages) that are showing the most marked increases in price.” Furthermore, this is far beyond inflation.
So what gives? Unfortunately the authors fail to provide a mechanism for this, but mind you is was published in a dietary journal, not one on economics. Maybe someone here can provide some insight where they (and myself) can’t?