The right breakfast: whole-grain barley or rye bread

10 September, 2007

Eating whole-grain barley or rye bread at breakfast is good for health, since it helps keep blood sugar in check the whole day.

Breads made from whole-grain barley or rye contain a combination of low glycemic index (GI) and certain type of indigestible carbohydrates that occur in certain grain products.

Glycemic index is a measure of how rapidly the level of blood sugar rises after ingestion of food containing carbohydrates.

The study, carried out by Anne Nilsson, a doctoral student at the Unit for Applied Nutrition and Food Chemistry at Lund University, Sweden, noted that it was the first time that it had been found that the benefits of a carbohydrate-rich breakfast with low GI lasts till after dinner.

The rapidity of the increase depends on how long it takes for the body to break down the carbohydrates in the intestines to glucose and then absorb
the glucose into the blood. When one eats products with a low GI, the blood sugar level rises slowly and the insulin increase is lower. Foods with low GI offer several health advantages.

“It is known that,” says Anne Nilsson, “a carbohydrate-rich breakfast with low GI can moderate increases in blood sugar after lunch. But my results show that low GI 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.”

Anne Nilsson carried out the study on four types of grains, in which barley clearly showed the best results.

The study shows that even people who have had a breakfast low in GI find it easier to concentrate for the rest of the morning.

Great variations in levels of blood sugar are being associated more and more with the risk of old-age diabetes, obesity, and cardiovascular diseases.

These findings can, therefore, provide valuable information for tailoring a new generation of whole-grain products with low GI that can counteract these
so-called lifestyle diseases. They may also have a beneficial effect on short-term memory and mental acuity.

Experiments also showed that the increase in blood sugar following breakfast can be moderated in a similar way by eating the right grain products the night before.

Barley showed clearly the best results of the four types of grain. In her test, Anne Nilsson used boiled grains and whole grains in bread.

But, when the grain was ground into porridge, the effect was weakened, since key structures were then destroyed, which had a negative effect on both GI and the content of resistant starch. On the contrary, splitting the grain worked fine.

The study also revealed that the right grain can have a favorable impact on the metabolic syndrome, which is a ‘catch-all’ name for a condition involving severe risk of diabetes and cardiovascular diseases.

The diagnosis includes heightened levels of blood sugar and insulin, raised blood fats, high blood pressure, and abdominal fat.

Indigestible carbohydrates ferment in the large intestine. This bacterial process proved to have a beneficial effect on a number of risk factors for metabolic syndrome, such as markers for inflammation and level of insulin efficiency. The process also produced a greater sense of satiety.

Anne Nilsson also studied the connection between mental acumen and blood sugar levels after meals. Trial subjects were given experimental breakfasts with low and high GI, respectively, and afterwards they were asked to perform mental acuity tests.

It was found that subjects who had eaten low GI breakfasts could concentrate better and had a better working memory (a type of short-term memory) than the other group. These experiments also showed that a healthy individual with low glucose tolerance, that is, with high rises in blood sugar than average following a meal, generally performed less well.