Eating breakfast cereal, especially whole grain cereal, may reduce the risk of developing high blood pressure, a new study suggests.
"We found about a 20% decreased risk of developing hypertension in those who consumed whole grain breakfast cereals at least seven times a week," said lead researcher Dr Jinesh Kochar, of Beth Israel Deaconess Medical Centre in Boston and the VA Boston Healthcare System.
"Along with other healthy lifestyles, such as low sodium intake and physical activity, getting whole grain from this readily available source can cut down the risk of developing chronic hypertension," he added.
Findings from the study, which received no private industry funding, were scheduled for presentation Tuesday at an American Heart Association conference in Atlanta.
For the study, Kochar's team collected data on 13,368 male doctors who took part in the Physicians Health Study I, a landmark trial begun in 1982.
None of the men had high blood pressure at the start of the study, but during more than 16 years of follow-up, 7,267 men developed hypertension, the researchers found.
High blood pressure, which puts people at risk for heart disease and stroke, is a leading cause of death in the United States.
The men were separated into four groups based on their cereal consumption.
When researchers adjusted only for age, they found that the men who ate cereal at least once a week reduced their risk of high blood pressure 8% compared with men who ate no cereal. Consuming cereal two to six times a week lowered the risk 16%, and eating it seven or more times a week dropped the risk 25%.
Small but significant result
When Kochar's group adjusted their findings to take into account smoking history, weight, alcohol intake, fruit and vegetable consumption, physical activity and history of diabetes in addition to age, the difference was still significant but smaller, 12% for those eating two to six servings a week and 19 percent for men eating seven or more bowls.
The association with lower blood pressure was stronger for whole grain cereals than refined grain cereals, the researchers found.
Kochar speculates the effect is partly because of whole grain cereal's high fibre content. Whole grains are also a good source of micronutrients, and they increase insulin sensitivity and reduce inflammation, he said.
Commenting on the study, Dr David L. Katz, director of the Prevention Research Centre at Yale University School of Medicine, said that "there has long been evidence that whole grain intake can lower blood pressure fairly acutely, and it is associated with lower blood pressure over time."
A number of mechanisms may produce this beneficial effect, he said. "They contain vitamins and minerals, such as potassium, that may directly relax blood vessels," Katz said. Another contributing factor is soluble fiber, "which helps lower blood sugar, lipid and insulin levels, and, in turn, lowers blood pressure," he added.
There's another obvious, but often overlooked explanation, Katz said: "Eating more whole grains means eating less of something else."
"When one considers the many high-sodium fast-food breakfast options, it may be as much what a bowl of cereal knocks out of one's diet, as what it puts in, that helps lower blood pressure and enhance health," Katz said.
More cereal might mean fewer scones and donuts, for example.
Experts note that research presented at meetings has not been subjected to the same type of rigorous scrutiny given to research published in peer-reviewed medical journals.
(Reuters Health, Steven Reinberg, March 2011)