“Think of the starving children in Africa!” Remember when that was how mom got you to clean your plate? These days, feeding the world’s hungry might have more to do with watching our waist — not just our waste. Obesity now poses more of a threat to global food security than overpopulation, according to a new study.

Historically, public health officials have focused on the number of “mouths to feed” as the main challenge to global food supply and production. Approaching from a different angle, British researchers suggest that the increased food demands of another billion “mouths to feed” would literally be outweighed by the fat mass of an increasingly overweight population. In the U.S. alone, where 80% are overweight, the calories needed to maintain obesity would feed 26 million additional “mouths.” For a list of ten fattest, and ten lightest nations, see below.

Sarah Walpole, MD, co-author of the study published in Biomed Central Public Health explains, “A heavier body needs more food to be sustained” — which in turn drives up demand for food, packaging, transport and energy. Obesity taxes global resources in other ways, as extra pounds increase the risk of a variety of expensive ailments, such as diabetes, heart disease, and cancer — which is why health care costs for the obese are growing almost three times as fast as those for normal-weight people.  Addressing these problems won’t be simple, but by factoring in over-consumption — and not just overpopulation, we may shift the debate, and search for solutions, in a more meaningful direction.

Published August 1, 2012