The BMJ (British Medical Journal) published the results of the PURE (Prospective Urban and Rural Epidemiology) study on February 03, 2021, which aimed to assess the relationship between the consumption of refined grains, whole grains and white rice with cardiovascular disease, all-cause mortality, blood lipids and blood pressure. The main outcome measure was the composite of mortality or major cardiovascular events (defined as death from cardiovascular causes, non-fatal myocardial infarction, stroke, or heart failure).
The study involved 148,858 participants from 21 countries with a median follow-up of 9.5 years. Country specific validated food frequency questionnaires were used to assess intakes of refined grains, whole grains, and white rice. Products in the refined grains category included white bread, pasta/noodles, breakfast cereals, crackers, and bakery products/desserts containing refined grains and others made with refined (white) flour. White rice was examined separately from all other refined grains because more than 60% of the PURE population reside in Asia where rice is a staple food.
Analyses were based on 137 130 participants after exclusion of those with baseline cardiovascular disease. During follow-up, 9.2% (n=12 668) of these participants had a composite outcome event. The highest category of intake of refined grains (≥350 g/day or about 7 servings/day) was associated with higher risk of total mortality (hazard ratio 1.27, 95% confidence interval 1.11 to 1.46; P for trend=0.004), major cardiovascular disease events (1.33, 1.16 to 1.52; P for trend<0.001), and their composite (1.28, 1.15 to 1.42; P for trend<0.001) compared with the lowest category of intake (<50 g/day). Higher intakes of refined grains were associated with higher systolic blood pressure. No significant associations were found between intakes of whole grains or white rice and health outcomes.
High intake of refined grains was associated with higher risk of mortality and major cardiovascular disease events.
https://www.bmj.com/content/372/bmj.m4948
BMJ 2021; 372 doi: https://doi.org/10.1136/bmj.m4948
