New research suggests that your breakfast cereal choice may affect how full you feel and how much you eat for lunch, especially if you're overweight.

Researchers from the New York Obesity Nutrition Research Center at Mount Sinai St. Luke's Hospital found that  having oatmeal (Quaker Oats Quick 1-minute^TM) for breakfast resulted in greater fullness, lower hunger ratings and fewer calories eaten at the next meal compared to a calorie-matched breakfast of a ready-to-eat cereal (RTEC) -- sugared corn flakes.

"Our results show that despite eating the same number of calories at breakfast, satiety values were significantly greater after consuming oatmeal compared to sugared corn flakes," said Allan Geliebter, lead researcher of the study.

For the study, Geliebter and his colleagues randomly assigned 36 subjects (18 normal weight and 18 overweight) to each receive three different breakfasts. The breakfasts consisted of 350 calories of similar amounts of carbohydrates, fat and liquid from either quick-cook oatmeal or sugared corn flakes. A third control breakfast was only 1.5 cups of water.

To evaluate appetite, ratings of hunger and fullness were obtained at frequent intervals before and after the breakfast until a lunch test meal 3 hours later. Researchers measured the calorie intake of the lunch meal consumed to compare the effects of the corn flakes, oatmeal or water breakfasts. Blood samples were collected just after each of the appetite ratings to assess levels of glucose, insulin, acetaminophen (a marker for how quickly the breakfast emptied from the stomach into the intestine) and various hormones related to appetite, in response to each breakfast.

The results showed statistically significant higher ratings of fullness, lower ratings of hunger, and 31 percent fewer calories consumed at lunch after consuming oatmeal compared to sugared corn flakes or water. The overall satiety effect was greater among overweight subjects, who consumed 50 percent fewer calories at lunch after eating oatmeal.

"Interestingly, the results were more pronounced for the participants who were overweight, suggesting that overweight individuals may be more responsive to the satiety effects of the dietary fiber in oatmeal," Geliebter said.

Based on their findings, researchers suggests that the greater satiety effect of oatmeal cereal compared to sugared corn flakes or water might be due to a slower gastric emptying (oatmeal took longer to leave the stomach). Given that the results were more pronounced in overweight subjects, researchers suggested that a longer-term weight control study testing daily oatmeal for breakfast is warranted.

The findings are detailed in the journal Annals of Nutrition and Metabolism.