Bumping up whole grain intake even slightly may lower the risk of death from heart disease, cancer and other chronic diseases, according to review published today in The British Medical Journal.

The new report echoes a study released Monday in the journal Circulation in which every additional serving of whole grains cut cardiovascular disease-related death risk by 9 percent and cancer death risk by five percent.

One serving of whole grains can be a half-cup of cooked brown rice, cooked oatmeal, or cooked 100 percent whole grain pasta, or one slice of 100 percent whole grain bread.

The BMJ review covered 45 studies involving more than 700,000 people altogether, and 100,000 deaths during follow-up. Researchers found the biggest difference in risk between people who ate two servings of whole grains per day and those who ate none. People who got two servings per day had lower risks of coronary heart disease, cardiovascular disease, death from stroke, cancer, respiratory disease, infectious disease and diabetes.

"The current study provides the most comprehensive assessment of whole grain intake and mortality to date and suggests that there are benefits of eating large amounts of whole grains for many different disease and mortality outcomes," including respiratory and infectious diseases which were not assessed in previous reviews, said lead author Dr. Dagfinn Aune of Imperial College London.

"Most likely the whole package of beneficial components in whole grains is the key, and therefore it is important to eat more whole grain foods rather than increasing intake of single nutrients from supplements," Aune told Reuters Health by email.

Breakfast cereals, whole grain breads and bran were associated with reduced risk of cardiovascular disease, he said, but specific grain types haven't been studied in as much detail as whole grains in general.

The Circulation paper is very similar to the one in BMJ because "both especially find lower mortality of cardiovascular disease," said Cecilie Kyro of the Danish Cancer Society Research Center, who coauthored an editorial alongside The BMJ review.

Increasing whole grain intake will be beneficial for most people, especially in countries where intake in low, like the U.S. and UK, Kyro told Reuters Health by email.