Eating a healthy breakfast could help tackle childhood obesity, researchers say.
Porridge was praised as a healthy breakfast choice
They found a breakfast with a low glycemic index - such as bran, porridge or muesli - is better than sugary cereals or white bread.
It means children eat less for lunch and tend not to snack between meals.
The researchers, from Oxford Brookes University, say the findings could help dieticians devise the most effective diets to combat child obesity.
The researchers studied 37 children aged nine to 12 to see what effect eating different foods for breakfast had on their hunger levels during the day.
They were given meals measured using the glycemic index (GI), which compares the rise in blood glucose levels after eating different foods.
One group had a low GI breakfast of muesli, porridge, a bran-based cereal or soya and linseed bread, with a GI value of less than 55.
A second group had a low GI breakfast with added sugar, with a value of above 55.
A third group was given a high GI breakfast of white bread, a cereal such as cornflakes or a chocolate-flavoured cereal with a GI value of between 75 and 100.
Each child ate each type of breakfast for three days in a row with about five weeks between testing.
They were monitored during each study session, asked how hungry they felt during the day and watched at lunchtime to see how much they ate.
The researchers found eating a low GI breakfast meant children ate significantly less for lunch than those who had a high GI meal for breakfast.
They were also less likely to feel hungry between meals.
The researchers hope the study will help dieticians prescribe a diet which releases sugar steadily throughout the day rather than in "quick fix" snacks.
Professor Jeya Henry, who led the research, said: "The study is remarkable for two reasons - firstly, that by selecting the type of breakfast we feed our children we can alter their subsequent food intake.
"Secondly, we now know that feeding children a low glycemic breakfast will reduce their food intake at lunch.
"Feeding them a high glycemic index breakfast will mean they will eat more."
A spokeswoman for the British Nutrition Foundation told BBC News Online: "The cereal foods that tend to be lower in glycemic index tend to be those which are higher in fibre, so things like whole grain cereals have numerous benefits for health.
"This goes along with the general healthy eating message.
"The thing we encourage above all else is that children should eat breakfast because that's important for performance at school, but these high fibre, low GI breakfasts are the best kind."
The study is published in the US journal Pediatrics.