ST. PAUL, Minn., March 26 (UPI) -- While it seems like a contradiction, many obese people do not enjoy eating rich, calorie-laden foods. A study published Wednesday indicates that low levels of a key brain chemical among overweight patients with high-fat diets is responsible for a loss of pleasure from food. Advertisement Researchers from the University of California-Berkeley say they may have found why people with obesity have been shown to take less pleasure in eating fatty foods than those