A recent Atlantic Monthly has an article by Elaine Shell of Boston University republished here in Australia about the obesity epidemic. She says that for the first time in history the number of people worldwide who are both overweight and malnourished (1.1bn) equals the number who are underweight and malnourished. The article by Shell centres on Kosrae, a 15km x 12km Pacific island, once a US colony, now politically independent, but still economically dependent on US aid. The article begins by setting the scene and describes how disbursing US aid has created sedentary office jobs that have replaced more physically demanding farming and fishing ... which also produce high quality foods. The Kosraeans have been seduced by highly processed, imported snack foods, particularly turkey tails, a fatty, gristly hunk of the bird which is regarded as inedible in the West. About 90 per cent of adult surgical admissions are for amputations due to vascular breakdown linked to diabetes. You can enter any clinic and smell the decaying limbs rotted by diabetes. Heart attacks often begin before people reach 30 years of age. Enough of the background; on to the evolutionary science. James Neel, a Michigan geneticist, hypothesized in 1962 that, under conditions of scarcity, natural selection weeds out people unable to store calories and that a thrifty genotype encourages the conversion of calories into body fat. Neel suggested that this mechanism was necessary for survival in periods of extreme stress and famine that would otherwise ravage a population. It is likely that peoples like the Kosraeans whose evolution was frequently punctuated by famines developed the most effective calorie storage. The very genes that protected islanders from their endemic famines now predispose them to life threatening illnesses. In 1994 a New York team cloned the ultimate thrifty gene, the obese gene, which carries the chemical code for the potent hormone leptin. Leptin plays a role in regulating appetite and fat storage. People who carry the abnormal form of the obese gene do not have the genetic makeup to produce leptin; they eat uncontrollably and are morbidly obese. All of us have variations along the leptin producing gradient. On Kosrae, people with more European inheritance and less of the famine protecting genetic makeup are less likely to be obese or diabetic. The article goes on to describe how public health programs fail and how the Kosraeans are beholden to the government and the government to the food and lifestyle importers. Solutions? Only Singapore seems to have the governmental, community and individual willpower to fight obesity successfully: their Trim and Fit program has halved childhood obesity in eight years. (Note: the above article includes direct quotes. I am not normally a plagiarist, but as the mail server does not reproduce inverted commas in e- mails to subscribers, I have not distinguished my own words from quotations.) Keith