Whole grains linked to a longer life

Analysis by Harvard researchers has found that eating more whole grains may reduce the risk of premature death. The meta-analysis, by researchers from Harvard T.H. Chan School of Public Health, found that people who ate the most whole grains (70 grams/day, about four servings), compared with those who ate little or no whole grains, had a lower risk of dying during the study period.

“These findings further support current dietary guidelines that recommend at least three daily servings (48 grams) of whole grains to improve long-term health and prevent premature death,” said Qi Sun, assistant professor in the Department of Nutrition and senior author of the study.

Previous studies have found that whole grains may reduce risk of cardiovascular disease (CVD), diabetes and poor gut health, among other conditions.

The meta-analysis, results of which will be published in Circulation, combined results from 12 published studies, in addition to unpublished results from the National Health and Nutrition Examination Survey (NHANES) III and NHANES 1999–2004. The studies were conducted in the United States, the United Kingdom or in Scandinavian countries between 1970 and 2010 and include health information from 786,076 participants.

The results showed that people who ate 70 grams/day of whole grains, compared with those who ate little or no whole grains, had a 22% lower risk of total mortality, a 23% lower risk of CVD mortality and a 20% lower risk of cancer mortality.

The researchers note that multiple bioactive compounds in whole grains could contribute to their health benefits, and that high fibre content may lower cholesterol production and glucose response and increase satiety.

The researchers recommend that people choose foods that are high in whole grain ingredients — such as bran, oatmeal and quinoa — while reducing consumption of refined carbohydrates.

One limitation of the meta-analysis was that some of the studies used were carried out before a more consistent definition of whole grains became available; therefore, lists of whole grain foods varied substantially among individual studies.