Flashback Friday: Plant-Based Diets for Diabetes

I’ve talked about the role meat may play in increasing the risk of diabetes, and the potential protective role of healthy plant foods. But plant-based diets not only appear to guard against getting diabetes in the first place, they may successfully treat the disease better than the diabetic diets patients are typically placed on, controlling weight and cholesterol.

Diets based on whole plant foods can result in significant weight loss without any limits on portion size or calorie counting, because plant foods tend to be so calorically dilute. Here’s a 100 calories of broccoli, tomatoes, strawberries, compared to a 100 calories of chicken, cheese, or fish. People just can’t seem to eat enough to compensate for the calorie deficit.

And, most importantly, it works better. A plant-based diet beat out the conventional American Diabetes Association diet in a head-to-head randomized controlled clinical trial, without restricting portions, no calorie or carb counting. A review of all such studies found that individuals following plant-based diets experience improved reductions in blood sugars, body weight, and cardiovascular risk, compared with those following diets that included animal products.

And, cardiovascular risk is what kills diabetics. More likely to get strokes, more likely heart failure. In fact, diabetes has been proposed as a coronary heart disease risk equivalent, which means diabetic patients without a history of coronary disease have an equivalent risk to that of non-diabetic individuals with confirmed heart disease.

A newer study used a technique to actually measure insulin sensitivity. Improved on both diets in the first three months, but then the veg diet pulled ahead. And, look at their LDL cholesterol. That’s what we see when people are put on plant-based diets; cholesterol comes down so much it can actually reverse the atherosclerosis progression, reverse the progression of heart disease.

We know about the beneficial effect of a vegetarian diet on controlling weight, blood sugars, cholesterol, insulin sensitivity, and oxidative stress compared to conventional diabetic diets, but what about quality of life, mood. How did people feel after making such a dramatic change in their diets? In this randomized controlled trial, study subjects were assigned either to a plant-based diet group or control group. Vegetables, grains, beans, fruits, and nuts with animal products limited to a maximum of one daily portion of low-fat yogurt, and the control group got the official diabetes diet.

Quality of life improved on both diets in the first three months, but within six months, the plant-based group clearly pulled ahead. Same thing with depression scores. Dropped in both groups in the first three months, but started to rebound in the control group.

Bottomline, the more plant-based diet led to a greater improvement in quality of life and mood. Patients consuming a vegetarian diet also felt less constrained than those consuming the conventional diet. People actually felt the conventional diabetic diet was more restrictive than the plant-based diet. Disinhibition decreased with a vegetarian diet, meaning those eating vegetarian were less likely to binge, and the veg group folks tended to feel less hungry, all of which helps with sustainability in the long term. So, not only do plant-based diets appear to work better, but they may be easier to stick to. And, with the improvement in mood, patients may exhibit desired improvements not only in physical, but also in mental health.

To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video. This is just an approximation of the audio contributed by Katie Schloer.

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