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I've heard it mentioned regularly that India and China are going through diabetes epidemics.
The reason I am given is because of the raised standard of living means people are now eating large quantities of white rice and because of its apparent sugar content it is causing an increase in the number of people with diabetes.
Is there any thorough research to indicate that the regular consumption of white rice causes a high risk of diabetes?
A US study (200000 participants) published in 2010 found a link between white rice and diabetes (actually between refined carbs and diabetes) :
From White Rice, Brown Rice, and Risk of Type 2 Diabetes in US Men and Women
Results After multivariate adjustment for age and other lifestyle and dietary risk factors, higher intake of white rice (≥5 servings per week vs <1 per month) was associated with a higher risk of type 2 diabetes: pooled relative risk (95% confidence interval [CI]), 1.17 (1.02-1.36)
...
Conclusions 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
In terms I better understand, from the BBC based on the same study:
After adjusting for age and other diabetes risk factors, those who ate five or more 150g servings of white rice per week had a 17% increased risk of diabetes compared with people who consumed less than one serving - about a cup of rice - per month.
Although few people - only 2% - in the study ate this much white rice, the finding was significant.
So the real link is between foods with a high Glycemic Index and diabetes.
Glycemic index, glycemic load, and risk of type 2 diabetes
During the past decade, several lines of evidence have collectively provided strong support for a relation between such diets and diabetes incidence. In animals and in short-term human studies, a high intake of carbohydrates with a high glycemic index (a relative measure of the incremental glucose response per gram of carbohydrate) produced greater insulin resistance than did the intake of low-glycemic-index carbohydrates. In large prospective epidemiologic studies, both the glycemic index and the glycemic load the glycemic index multiplied by the amount of carbohydrate) of the overall diet have been associated with a greater risk of type 2 diabetes in both men and women.
The cause of diabetes appears to be a combination of a high fat diet in conjunction with reduced exercise. Populations that have had historically high carbohydrate intake have not been prone to diabetes so this theory of a high white rice diet is likely incorrect without other factors being present. The prevalence of diabetes in China in 1980 was estimated at < 1%, 2.5% in 1994, 5.5% in 2001, and 11.6% in 2013 [0] illustrating how dietary changes have impacted on disease prevalence.
If we look at animal studies where rats are fed high fat diets, we see:[1]
a high-fat diet that raises FFA results in a gradual increase in mitochondria in rat skeletal muscle, with an increase in the capacity for fat oxidation, concomitant with development of muscle insulin resistance.
Skeletal muscle insulin resistance then facilitates the development of fatty liver during positive energy balance ( eating too much, not enough exercise ). [2]
Muscle insulin resistance determines the rate at which fatty liver progresses, and ectopic fat deposition in liver and islet underlies the related dynamic defects of hepatic insulin resistance and beta cell dysfunction.
The fatty liver leads to loss of response to insulin so that hepatic synthesis of glucose is no longer suppressed, and the higher levels of glucose induce higher levels of pancreatic insulin release. The fatty liver also raises plasma triacylglycerols which in turn are toxic to pancreatic beta cells. The accumulation of triacylglycerols in the pancreas, as well as the circulating high levels cause beta cell dysfunction which then leads to a fall in insulin release, and this allows an even higher rate of hepatic glucose synthesis.
The rapid restoration of hepatic sensitivity to insulin following gastric bypass surgery shows that the process is potentially reversible in the early stages before permanent pancreatic beta cell failure occurs.
[0] Xu Y, Wang L, He J, [..], Ning G. Prevalence and control of diabetes in Chinese adults. JAMA. 2013 Sep 4;310(9):948-59. doi: 10.1001/jama.2013.168118. PubMed PMID: 24002281.
[1] Hancock CR, Han DH, Chen M, [..], Holloszy JO. High-fat diets cause insulin resistance despite an increase in muscle mitochondria. Proc. Natl. Acad. Sci. U.S.A. 2008 Jun 3;105(22):7815-20. doi: 10.1073/pnas.0802057105. PubMed PMID: 18509063.
[2] Taylor R. Pathogenesis of type 2 diabetes: tracing the reverse route from cure to cause. Diabetologia. 2008 Oct;51(10):1781-9. doi: 10.1007/s00125-008-1116-7. PubMed PMID: 18726585.
