Refined Grains Found to Contribute to Cardiovascular Disease

Much research has been done to support the notion that a diet rich in whole grains prolongs life, but how does eating mainly refined grains affect one’s health? A new study published in the BMJ examined diets around the world to determine how nutrition impacts the risk of cardiovascular disease and mortality. Researchers compared the diets of those who consumed mostly refined grains, whole grains, and white rice. Past studies have shown that higher whole grain intake is linked with lower risk of cardiovascular disease and death, but the association between refined grains and health risk had been left unclear.

Data was collected on 137,130 people aged 35 to 70 years across 21 low-, middle-, and high-income countries. Participants had no history of heart disease and were taking part in the Prospective Urban and Rural Epidemiological study, a large-scale study that examined the relationship of societal influences on behaviors, cardiovascular risk factors, and chronic disease.

Wealth, lifestyle, medical history, and food questionnaires were collected at the start of the BMJ study. Deaths from cardiovascular causes or serious cardiovascular events, including heart attack, stroke, and heart failure, were tracked over an average of 9.4 years.

It was found that those with the highest intake of refined grains, which was at least 350 grams or about seven servings per day, had a 27% higher risk of death and a 33% higher risk of serious cardiovascular events than the lowest category—those who ate less than 50 grams per day. Higher consumption of refined grains was also associated with higher blood pressure. No significant associations were found between intakes of whole grains or white rice with health outcomes.

The study was observational in nature and cause could not be established, but as the data was collected across five continents, researchers were able to analyze broad patterns of diet. The results are widely applicable to populations across the world, so researchers concluded that a lower intake of refined products and higher intake of whole grains should be encouraged globally.