Various studies have shown that those who follow a plant-based, or mostly-plant-based diet, can lower body weight and decrease blood sugar, lowering the risk of diabetes.
The 2011 Adventist Health study was the first prospective study (the researcher follow a group of participants over time) to look at the incidence of diabetes in vegans. The study showed that vegans have a 60% lower risk of diabetes compared to non-vegans. The authors attributed the decreased incidence of diabetes to an increased consumption of fruits and vegetables with their lower calorie consumption, increased fiber content and lower glycemic load. They also felt that the whole grains and legumes may have helped to reduce the rate of carbohydrate absorption thereby lowering the risk of diabetes.
More research from the Advent Health Study in 2009 was not prospective, but cross-sectional (provides a "snapshot" of the frequency and characteristics of a disease in a population at a particular point in time), and also looked at the risk of diabetes in vegans. This study showed that vegans had a 68% lower risk of diabetes compared to non-vegans. (PCRM) conducted a 74 week study in 2004 with 99 participants comparing a low fat vegan diet (and low glycemic foods) to the American Diabetes Association (ADA) diet for folks with diabetes. The vegan group ate less calories and lost weight as their fiber and carbohydrate intake went up. Their HbA1C and blood sugar decreased and many participants were able to decrease their diabetes medication. The ADA group also saw improvements, however the vegan group lost more weight.
What to take from this research? Consuming more fiber-rich plants, whole fruits (not juice), whole grains, and legumes may help prevent or control diabetes. Plus there are multitude more reasons to eat more plants with powerful phytochemicals that prevent even more chronic diseases such as heart disease and cancer.
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