Why The Latest White Rice = Diabetes Study Is Hogwash

Following the recent red-meat study, the media is hot on its heels with more alarmist headlines this time about white rice and diabetes risk.  But what does the study really show? Is this a serious finding with serious implications? Or just bad science as usual?

The Study

Published in The British Journal of Nutrition, researchers from Harvard conducted a meta-analysis of observational studies investigating white rice consumption and type-2 diabetes (T2D) risk [1]. They identified 4 studies that met their criteria. In a pooled analysis of 7 cohorts including over 350,000 subjects, and some 13,000 cases with a follow-up period of 4-22 years, they found a higher consumption of white rice was associated with increased T2D risk (RR = 1.27; 1.04-1.54). When stratified by ethnicity, increased risk was especially apparent Asian populations (RR = 1.55; 1.20-2.01) and to a nonsignificant degree also in Western populations (RR = 1.12; 0.94-1.33).

Garbage In, Garbage Out...

Now here’s why I can’t take this study seriously, at all. In the 7 cohorts they analyzed, 6 did not adjust for socioeconomic status. The authors of this meta-analysis say themselves:

Confounding by socioeconomic status is of particular concern because this is both a risk factor for type 2 diabetes and a predictor of rice consumption in Asian and Western populations.

Secondly, NONE of the studies were seriously adjusted for other refined sugar dietary variables. Heck, one study didn’t even adjust for a family history of T2D!

This sloppy statistical work casts an inexcusable shadow of doubt over their conclusions and thus this study cannot be taken seriously. In colloquial statistics lingo, this was a ‘GIGO meta-analysis’. That is, if you put garbage into a meta-analysis, your only going to get garbage out.

Think Twice About White Rice?

Nah. This meta-analysis did not present any compelling evidence that higher consumption of white rice was associated with an increased risk of T2D. The fact that patently influential confounders were left unadjusted renders this study flawed in its very structure. The real disappointment was that the authors make no real attempt to redress or even discuss these disabling limitations. As a result, we have headlines that are awash with sensationalistic bogus once again. Forget the bad science, keep eating your white rice.

Picture courtesy of “Ray_from_LA“.