A new global study reveals that many refined-flour foods are associated with a higher risk of major cardiovascular disease, stroke and early death when compared to whole grains. 

The study published in The British Medical Journal found that having more than seven servings of refined grains per day was associated with a 27 percent greater risk for early death, 33 percent greater risk for heart disease and 47 percent greater risk for stroke.

However, no significant adverse health effects were found with consuming white rice or whole grains.

The study based its findings on data from the Prospective Urban Rural Epidemiology (PURE) study, which tracked the diets of 137,130 participants in 21 countries over 16 years. 

In addition to its primary findings, the study found that the intake of refined grains and added sugars have greatly increased over the years throughout the PURE study cohort. 

No significant adverse health effects were found with consuming white rice or whole grains.Less refined is more
The study suggests that healthy diets should include more whole-grain foods like brown rice and barley while limiting cereal grains and refined wheat products. 

“This study re-affirms previous work indicating a healthy diet includes limiting overly processed and refined foods,” says Scott Lear, a co-author of the study and health sciences professor at Simon Fraser University in Burnaby, Canada. 

Reducing one’s overall consumption of refined grains and having better quality carbohydrates is essential for optimal health outcomes, the researchers write. 

What defines refined
Grains were categorized into three groups: refined grains, whole grains and white rice. 

White rice was assessed separately because more than 60 percent of the PURE population reside in Asia, where rice is a staple food, note the researchers. 

Refined grains included goods made with refined (white) flour, including white bread, pasta or noodles, breakfast cereals, crackers, and bakery products or desserts containing refined grains. 

Whole grains included whole grain flours, such as buckwheat, and intact or cracked whole grains, such as steel-cut oats.

Confusion for consumers?
There is no easy consensus from the health industry on refined flours’ total impact on health. 

New Dietary Guidelines for Americans, 2020-2025 recommend that US residents consume a mix of whole wheat and enriched, refined grains, three servings of each per day. 

The health of flour can also be manipulated via measures like fortification, which can provide important sources of nutrients. A recent German study casually correlated a decrease in cancer mortality in Finland, where flour is enriched with vitamin D.