As you can see in my video, Plant-Based Diets and Diabetes, we've known for decades that a plant-based diet may be protective against diabetes. Studies going back half a century found that those eating meat one or more days a week had significantly higher rates of diabetes, and the more frequently meat was eaten, the more frequent the disease. And this is after controlling for weight, so even at the same weight, those eating more plant-based had but a fraction of the diabetes rates. If anything, vegetarians should have had more diabetes just because they appear to live so much longer, so they had more time to develop these kinds of chronic diseases; but no, apparently lower rates of death and disease.
Fast forward 50 years to the Adventist-2 study, looking at 89,000 people, and we see a stepwise drop in the rates of diabetes as one eats more and more plant-based, down to a 78% lower prevalence among those eating strictly plant-based. Protection building incrementally as one moved from eating meat daily, to eating meat weekly, to just fish, to no meat, and then to no eggs and dairy either. Followed over time, vegetarian diets were associated with a substantially lower incidence of diabetes, indicating the potential of these diets to stem the current diabetes epidemic.
We see the same step-wise drop in rates of another leading killer, high blood pressure. The greater the proportion of plant foods, the lower the rates of hypertension, and the same with excess body fat. The only dietary group not on average overweight were those eating diets composed exclusively of plant foods, but again there was the same incremental drop with fewer and fewer animal products. This suggests that it's not black and white, not all or nothing, any steps we can make along this spectrum of eating healthier may accrue significant benefits.
What about eating a really healthy diet with just a little meat? Is it better to eat none at all? We have new insight last year from Taiwan. Asian diets in general tend to be lower in meat and higher in plant foods compared with Western diet, but whether a diet completely avoiding meat and fish would further extend the protective effect of a plant-based diet wasn't known, until now.
Traditionally, Asian populations have had low rates of diabetes, but a diabetes epidemic has since emerged, and appears to coincide with increased meat, animal protein, and animal fat consumption, but the Westernization of Asian diets also brought along a lot of fast food and junk, and so these researchers at the national university didn't want to just compare those eating vegetarian to typical meateaters. So, they compared Bhuddist vegetarians to Bhuddist non-vegetarians, eating traditional Asian diets. Even the omnivores were eating a predominantly plant-based diet, consuming little meat and fish, with the women eating the equivalent of about a single serving a week, and men eating a serving every few days. That's just 8% of the meat intake in the U.S., 3% for the women. The question: is it better to eat 3% or 0%?
Again, both groups were eating healthy; zero soda consumption, for example, in any group. Despite the similarities in their diet, and after controlling for weight, family history, exercise, and smoking, the men eating vegetarian had just half the rates of diabetes, and the vegetarian women just a quarter of the rates. So even in a population consuming a really plant-based diet with little meat and fish, true vegetarians who completely avoided animal flesh, while eating more healthy plant foods, have lower odds for prediabetes and diabetes after accounting for other risk factors. They wanted to break it up into vegan versus ovo-lacto like in the Adventist-2 study, but they couldn't because there were no cases at all of diabetes found within the vegan group.
More on preventing and treating this terrible disease:
- Preventing Prediabetes By Eating More
- Diabetics Should Take Their Pulses
- How to Prevent Prediabetes from Turning into Diabetes
- How to Prevent Prediabetes in Children
- Eggs and Diabetes
- Fish and Diabetes
- Flaxseed vs. Diabetes
- When Drugs & Diets Don't Lower Diabetes Deaths
- Diabetes Reversal: Is it the Calories or the Food?
- Reversing Diabetes with Food
The reason I keep going back to that Adventist-2 study is that it's not only the biggest study of those eating plant based diets in North America, but the largest such study anywhere anytime. We owe those investigators a great debt (not to mention the 96,741 participants!). One thing I'm happy my tax dollars are going towards (via the National Cancer Institute and National Institutes of Health). More from the Adventists in Caloric Restriction vs. Animal Protein Restriction.
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--2013: Uprooting the Leading Causes of Death, 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, and my latest, 2016: How Not To Die: The Role of Diet in Preventing, Arresting, and Reversing Our Top 15 Killers.
Image Credit: Reisek / Flickr