My Why Is Meat a Risk Factor for Diabetes? video shows how meat may play a role in increasing the risk of diabetes, and How May Plants Protect Against Diabetes? and Plant-Based Diets and Diabetes discuss 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 typically are placed on, benefiting both weight and cholesterol.

Diets based on whole plant foods can result in significant weight loss without limiting portion size or counting calories, because plant foods tend to be so calorically dilute. In my video Plant-Based Diets for Diabetes, you can see the volume of 100 calories of broccoli, tomatoes, and strawberries compared to 100 calories of chicken, cheese, or fish. People just can’t seem to eat enough of the plant foods to compensate for the calorie deficit, so they lose weight eating whole plant foods.

Most importantly, a plant-based diet 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 and without calorie- or carb-counting. A review of all such studies found that those following plant-based diets experience improved reductions in blood sugars, body weight, and cardiovascular risk, compared with those on diets including animal products.

Cardiovascular risk is what kills diabetics the most. They’re more likely to get strokes, more likely to suffer heart failure. In fact, “[d]iabetes 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 nondiabetic individuals with confirmed heart disease.”

A newer study used a technique to actually measure insulin sensitivity. It improved on both diets in the first three months, but then the vegetarian diet pulled ahead. The researchers also found that the LDL cholesterol fell significantly in the vegetarian group. Indeed, 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—that is, 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 and mental health? How did people feel after making such a dramatic change in their diets? In a randomized, controlled trial, study subjects were assigned either to a plant-based diet group or a control group. The plant-based group ate vegetables, grains, beans, fruits, and nuts with animal products limited to a maximum of one daily portion of low-fat yogurt. The control group followed an 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. The same results were seen with depression scores: they dropped in both groups in the first three months, but started to rebound in the control group.

The bottom line is that 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 subjects in the vegetarian group tended to feel less hungry. All of this helps with sustainability in the long term, which is, of course, critical for any dietary change. 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.

For those seeking a deeper understanding of what diabetes really is and what causes it, check out How Not to Die from Diabetes and this series of videos:

Thankfully, not only can diabetes be reversed, but so can some of its complications. See Can Diabetic Retinopathy Be Reversed? and, for diabetic neuropathy, my live annual review From Table to Able: Combating Disabling Diseases with Food.

Of course, preventing it is better:

There are some foods that may increase the risk:

And others that may help:

In health,

Michael Greger, M.D.