Eating large amounts of refined carbohydrates and foods with a high glycaemic index seems to be associated with an increased risk for certain conditions such as heart disease and type 2 diabetes. A study(1) recently published in the medical journal Archives of Internal Medicine has concluded that “Substitution of whole grains, including brown rice, for white rice may lower risk of type 2 diabetes. These data support the recommendation that most carbohydrate intake should come from whole grains rather than refined grains to help prevent type 2 diabetes”
The study (1) looked prospectively at diet, lifestyle practice and disease among over 39,000 men and 157,000 women. After analysing the data and making adjustments for age and other lifestyle and dietary risk factors the authors of the study found that a higher intake of white rice (5 or more servings per week compared to less than once per month) was associated with a higher risk of type 2 diabetes. In contrast, high brown rice intake (2 or more servings per week compared to less than once per month) was associated with a lower risk of type 2 diabetes. The scientists estimated that replacing 50 g per day intake of white rice with the same amount of brown rice was associated with a 16% lower risk of type 2 diabetes, whereas the same replacement with whole grains, such as wheat, barley and oats, as a group was associated with a 36% (30%-42%) lower diabetes risk.
The study is interesting since it is the first to specifically examine white rice and brown rice in relation to diabetes risk among Americans. The lead study author said in a press release (2) “Rice consumption in the U.S. has dramatically increased in recent decades. We believe replacing white rice and other refined grains with whole grains, including brown rice, would help lower the risk of type 2 diabetes,” I am sure that the same could be said for the UK. Brown rice contain more fibre, minerals, vitamins and phytochemicals (bioactive plant nutrients) than white rice and tends to have a lower glycaemic index, so does not generate as large an increase in blood sugar levels. Brown rice is processed, milled and polished to produce white rice, which removes most of the vitamins, minerals and fibre. For the classification of more food examples please visit the website ‘The Glycemic Index’, there you will find a database where you can search for specific foods and find out more about GI and health. For past blog posts on glycaemic index please click here
The study authors say (2) “From a public health point of view, whole grains, rather than refined carbohydrates, such as white rice, should be recommended as the primary source of carbohydrates for the U.S. population,” “These findings could have even greater implications for Asian and other populations in which rice is a staple food.”
The study shows there is an association between whole grain intake and a reduced risk of type 2 diabetes, it does not prove that whole grains prevent the condition. However, the authors of the study did adjust for various factors such as: body adiposity (fat), smoking, physical activity, and other dietary factors, when analysing their results so the links between whole grains and prevention of type 2 diabetes appear quite strong. Type 2 diabetes is closely linked to being overweight as well as poor diet and lack of exercise and is becoming an increasingly common problem in the UK population.
It would make sense from a health perspective to replace refined carbohydrates with whole grains including rice, oats, barley, wheat, quinoa and millet. Whole grains are nutrient dense, they provide the vitamins, minerals, phytochemicals and fibre that is lacking in the white/refined varieties. Switching to wholegrain versions is an easy choice but packs a nutrient-rich punch!
(1) Sun Q et al. 2010. White Rice, Brown Rice, and Risk of Type 2 Diabetes in US Men and Women. Arch Intern Med. 170 (11): 961-969
(2)Press release: Harvard School of Public Health (2010, June 14). Replacing white rice with brown rice or other whole grains may reduce diabetes risk. ScienceDaily. Retrieved June 15, 2010, from http://www.sciencedaily.com /releases/2010/06/100614161349.htm
Written by Ani Kowal