The bad news: Eating large quantities of white rice increases the risk of developing type 2 diabetes. A recent article in The British Medical Journal presented this conclusion after its authors conducted a meta-analysis of prospective cohort studies on the topic. The researchers found that each daily serving was associated with an 11 percent increase in the risk of diabetes in the overall population.
Because white rice is a dietary staple of Asian countries such as China and Japan, the risk for those populations is greater than for Western countries whose citizens favor other grains. White rice in Asian countries composes the populations’ main dietary glycemic load; the study notes that glycemic load is consistently associated with increased risk of developing type 2 diabetes. The Chinese and Japanese typically eat three to four servings of white rice a day, while Westerners eat one to two servings a week.
Lifestyle changes in Asia contribute to diabetes risk
Rice consumption in Asian nations has always been high, but not so the risk of type 2 diabetes. “The recent transition in nutrition characterised by dramatically decreased physical activity levels and much improved security and variety of food has led to increased prevalence of obesity and insulin resistance in Asian countries,” the authors state. “Although rice has been a staple food in Asian populations for thousands of years, this transition may render Asian populations more susceptible to the adverse effects of high intakes of white rice, as well as other sources of refined carbohydrates such as pastries, white bread, and sugar sweetened beverages. In addition, the dose-response relations indicate that even for Western populations with typically low intake levels, relatively high white rice consumption may still modestly increase risk of diabetes.”
“Like many research findings, these results need to be put into context,” says Martha Johns, MD, MPH, FACPM, HealthTeamWorks medical director for Guidelines and Implementation. “As the researchers point out, modern cultural changes in Asian populations have led to increases in other refined carbohydrates, decreases in physical activity and increasing obesity, all of which are risk factors for diabetes. White rice is only one factor.”
Brown rice may lower risk of diabetes
What about brown rice? The data are limited but seem to indicate that consumption of brown rice may “modestly” lower the risk of type 2 diabetes. “More studies with larger sample sizes and longer durations of follow-up are warranted to examine the effects of substituting brown rice for white rice on risk of diabetes,” the researchers say.
HealthTeamWorks has just updated its clinical guideline on type 2 diabetes. All HealthTeamWorks guidelines are available for free download.
The upshot of this study for white rice lovers: Enjoy, but in moderation. This is good advice for nearly all foods.
Hu EA, Pan A, Malik V, Sun Q. White rice consumption and risk of type 2 diabetes: Meta-analysis and systematic review. BMJ 2012; 344 doi: 10.1136/bmj.e1454 (Published 15 March 2012)