Rice currently feeds almost half the human population, making it the single most important staple food in the world, but a meta-analysis of seven cohort studies following 350,000 people for up to 20 years found that higher consumption of white rice was associated with a significantly increased risk of type 2 diabetes, especially in Asian populations. They estimated each serving per day of white rice was associated with an 11% increase in risk of diabetes. This could explain why China has almost the same diabetes rates as we do.
Diabetes rates in China are at about 10%; we're at about 11%, despite seven times less obesity in China. Japan has eight times less obesity than we do, yet may have a higher incidence of newly diagnosed diabetes cases than we do--nine per a thousand compared to our eight. They're skinnier and still may have more diabetes. Maybe it's because of all the white rice they eat.
Eating whole fruit is associated with lower risk of diabetes, whereas eating fruit processed into juice may not just be neutral, but actually increases diabetes risk. In the same way, eating whole grains, like whole wheat bread or brown rice is associated with lower risk of diabetes, whereas eating white rice, a processed grain, may not just be neutral, but actually increase diabetes risk.
White rice consumption does not appear to be associated with increased risk of heart attack or stroke, though, which is a relief after an earlier study in China suggested a connection with stroke. But do we want to eat a food that's just neutral regarding some of our leading causes of death, when we can eat whole foods that are associated with lower risk of diabetes, heart attack, stroke, and weight gain?
If the modern diabetes epidemic in China and Japan has been linked to white rice consumption, how can we reconcile that with low diabetes rates just a few decades ago when they ate even more rice? If you look at the Cornell-Oxford-China Project, rural plant-based diets centered around rice were associated with relatively low risk of the so-called diseases of affluence, which includes diabetes. Maybe Asians just genetically don't get the same blood sugar spike when they eat white rice? This is not the case; if anything people of Chinese ethnicity get higher blood sugar spikes.
The rise in these diseases of affluence in China over the last half century has been blamed in part on the tripling of the consumption of animal source foods. The upsurge in diabetes has been most dramatic, and it's mostly just happened over the last decade. That crazy 9.7% diabetes prevalence figure that rivals ours is new--they appeared to have one of the lowest diabetes rates in the world in the year 2000.
So what happened to their diets in the last 20 years or so? Oil consumption went up 20%, pork consumption went up 40%, and rice consumption dropped about 30%. As diabetes rates were skyrocketing, rice consumption was going down, so maybe it's the animal products and junk food that are the problem. Yes, brown rice is better than white rice, but to stop the mounting Asian epidemic, maybe we should focus on removing the cause--the toxic Western diet. That would be consistent with data showing animal protein and fat consumption associated with increased diabetes risk.
But that doesn't explain why the biggest recent studies in Japan and China associate white rice intake with diabetes. One possibility is that animal protein is making the rice worse. If you feed people mashed white potatoes, a high glycemic food like white rice, you can see in my video If White Rice is Linked to Diabetes, What About China? the level of insulin your pancreas has to pump out to keep your blood sugars in check. But what if you added some tuna fish? Tuna doesn't have any carbs, sugar, or starch so it shouldn't make a difference. Or maybe it would even lower the mashed potato spike by lowering the glycemic load of the whole meal? Instead you get twice the insulin spike. This also happens with white flour spaghetti versus white flour spaghetti with meat. The addition of animal protein makes the pancreas work twice as hard.
You can do it with straight sugar water too. If you do a glucose challenge test to test for diabetes, where you drink a certain amount of sugar and add some meat, you get a much bigger spike than without meat. And the more meat you add, the worse it gets. Just adding a little meat to carbs doesn't seem to do much, but once you get up to around a third of a chicken breast's worth, you can elicit a significantly increased surge of insulin. This may help explain why those eating plant-based have such low diabetes rates, because animal protein can markedly potentiate the insulin secretion triggered by carbohydrate ingestion.
The protein exacerbation of the effect of refined carbs could help explain the remarkable results achieved by Dr. Kempner with a don't-try-this-at-home diet composed of mostly white rice and sugar. See my video, Kempner Rice Diet: Whipping Us Into Shape.
Refined grains may also not be good for our blood pressure (see Whole Grains May Work As Well As Drugs).
What should we be eating to best decrease our risk of diabetes? See:
- Plant-Based Diets and Diabetes
- Lifestyle Medicine Is the Standard of Care for Prediabetes
- Diabetics Should Take Their Pulses
- How to Prevent Prediabetes from Turning into Diabetes
- How to Prevent Prediabetes in Children
- What Causes Insulin Resistance?
- The Spillover Effect Links Obesity to Diabetes
- Lipotoxicity: How Saturated Fat Raises Blood Sugar
And check out my summary video, How Not to Die from Diabetes.
Michael Greger, M.D.
PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:
- 2012: Uprooting the Leading Causes of Death
- 2013: More Than an Apple a Day
- 2014: From Table to Able: Combating Disabling Diseases with Food
- 2015: Food as Medicine: Preventing and Treating the Most Dreaded Diseases with Diet
- 2016: How Not To Die: The Role of Diet in Preventing, Arresting, and Reversing Our Top 15 Killers
Image Credit: Sally Plank / Flickr. This image has been modified.