New research reveals how certain fatty foods help to regulate appetite. Writing in the journal Cell Metabolism, the Italian and American scientists explain how unsaturated fats, such as those found in olive oil, avocados and nuts, stimulate the production of a molecule that suppresses hunger pangs. The findings could lead to the development of new drugs to treat obesity and other eating disorders. Previous studies demonstrated that eating stimulates cells in the lining of the intestine to produce a hormone called oleoylethanolamide, or OEA. When administered as a drug, OEA reduces appetite, lowers blood cholesterol and promotes weight loss. In this latest piece of research, the scientists found that it is the fats in our diet that trigger the release of OEA; proteins and carbohydrates do not have the same effect, although proteins are known to regulate appetite via other means. Specifically, oleic acid, which is found in olive oil, is converted into OEA by cells in the upper reaches of the small intestine. From there, it makes its way to nerve endings that carry appetite-suppressing messages to the brain. In the brain, the message activates a circuit that generates sensations of fullness. The scientists believe that their findings could lead to the development of new treatments for obesity and other dietary disorders. Such drugs could control appetite by increasing OEA levels or blocking its breakdown. 'We are excited to find that OEA activates cell receptors that already have been the focus of successful drug development,' commented Professor Daniele Piomelli of the University of California, Irvine in the US. 'This gives us hope for a new class of anti-obesity drugs based on the savvy use of natural appetite-controlling mechanisms.' However, Professor Piomelli also warns that diets high in processed foods could interfere with this newly discovered system and so contribute to obesity. Processed foods are typically high in saturated fats but contain very little oleic acid. 'Eating is one of the most important things animals do,' he stated. 'This is just one of many things that control it. That said, a system like this could be forced to inactivation by inappropriate feeding.' Professor Piomelli is also keen to find out whether this system is defective in people who tend to eat to excess.
Italy, United States