Experiments also showed that the blood sugar increase following breakfast can be moderated in a similar way by eating the right grain products the night before, said study leader Anne Nilsson, a doctoral student at Lund University.

"It is known that a carbohydrate-rich breakfast with low glycemic index can moderate increases in blood sugar after lunch," Nilsson said in a statement.

"But my results show that low glycemic index in combination with the right amount of so-called indigestible carbohydrates, that is, dietary fiber and resistant starch, can keep the blood-sugar level low for up to 10 hours, which means until after dinner."

Barley had the best results of the four types of grain tested.

Glycemic index is a measure of how rapidly the level of blood sugar rises after ingestion of food containing carbohydrates. Foods with low glycemic index offer several health advantages because the blood sugar level rises slowly and the insulin increase is lower.