The marketing labels “organic”, “all natural”, and “whole grain” typically bear a positive connotation with broad appeal to health-conscious consumers. Do these foods truly have any health benefits? While “organic” and “all natural” properties of food may have unclear effects, there is mounting evidence that “whole grains” do. Harvard researchers recently compared whole-grain brown rice with refined white rice and evaluated their relative risks for developing type 2 diabetes.
The study analyzed prospective data from 39,765 men and 15,7463 women who participated in 3 separate cohort studies: the Health Professionals Follow-up Study (HPFS) and the Nurses’ Health Study (NHS) I and II. Relevant to this research study, the individual cohort studies had required periodic completion of questionnaires about lifestyle practices and occurrences of chronic diseases.
Individuals who did not complete over 50% of the food items on the food frequency questionnaire (FFQ) were excluded from this study’s analysis. In addition, the researchers excluded those with a pre-existing diagnosis of diabetes, cardiovascular disease, and cancer.
Adjusting for age alone, consumption of >4 servings/week of white rice was associated with a greater risk of developing type 2 diabetes, relative to those who eat <1 serving/month. There was a smaller but similar trend after adjusting for other potential confounders, such as ethnicity, body mass index, smoking status, alcohol intake, multivitamin use, physical activity, and family history of diabetes.
In contrast, consumption of >1 serving/week of brown rice was associated with a lower relative risk of type 2 diabetes, compared to those who eat <1 serving/month. When replacing 50 g/day of white rice with brown rice, there was a 16% decreased risk of diabetes. This risk was 36% lower when white rice was instead substituted with whole grains.
The authors hypothesize that the refinery process that converts brown rice to white rice leads to loss of some protective effects of bran, fiber, vitamins, minerals, lignans, phytoestrogens, and phytic acid.
The findings of this study reinforce that “substitution of whole grains, including brown rice, for white rice may lower risk of type 2 diabetes.” While physicians may counsel their diabetic patients to practice strict carbohydrate control, pre-diabetics should also consider the nutritional impact of their food choices. I will however admit that it is much easier said than done. My acquired taste for white rice is much stronger than for brown rice, and I fear my taste buds may revolt if I were to someday defect to the brown side.
- Source
- Sun Q, Spiegelman D, van Dam RM, Holmes MD, Malik VS, Willett WC, Hu FB. White rice, brown rice, and risk of type 2 diabetes in US men and women. Arch Intern Med 2010;170:961-9.
The “New & Interesting” series is a biweekly compilation of select research findings, news articles, and random tidbits in bullet-point format. The entries are highly abbreviated, but provide links to the original articles or abstracts if you desire to read further.
Low-carbohydrate diets were initially popularized by the late Dr. Robert Atkins, who published the fundamentals of this diet in his book Dr. Atkins’ New Diet Revolution. He also founded Atkins Nutritional to commercialize and further evangelize the low-carbohydrate diet. Following Dr. Atkins’s death, however, the popularity of the diet subsided and his company filed for Chapter 11 bankruptcy in 2005.
