A diet rich in fruit and vegetables is associated with substantially reduced risk of developing type 2 diabetes, a large body of research confirms.

Published in PLOS Medicine, the findings support current recommendations to eat healthy plant-based foods and moderate intake of red meat, particularly processed meat.

The Harvard researchers analysed data from three studies that followed more than 200,000 male and female health professionals in the US for more than 20 years, regularly collecting information on their diet, lifestyle, medical history and new disease diagnoses.

They found that having a diet rich in plant foods and low in animal foods was associated with a reduction of about 20% in the risk of diabetes.

“Consumption of a plant-based diet that emphasised specifically healthy plant foods [such as fruit and vegetables] was associated with a larger decrease (34%) in diabetes risk, while consumption of a plant-based diet high in less-healthy plant foods [such as refined grains and fruit juices] was associated with a 16% increased diabetes risk,” write the authors.

“Our study highlights the varying risk profiles associated with different versions of plant-based diets, emphasising the importance of considering the quality of the plant foods consumed.

“We also found that even a modest lowering in animal food consumption was associated with substantially lower type 2 diabetes incidence.”

They attribute the reduction of type 2 diabetes risk to enhanced glycemic control, improved insulin sensitivity and decreased chronic inflammation.

In addition, they say the high fibre and low calorie contents of many plant foods could further reduce disease risk by promoting weight loss.

But there could be another less well understood mechanism at work, the authors add.

“A healthful plant-based diet could promote a gut microbial environment that facilitates the metabolism of fiber and polyphenols and discourages the metabolism of bile acids, choline and L-carnitine, and amino acids, further reducing type 2 diabetes risk.”

Last Reviewed: 24/06/2016



Plant-Based Dietary Patterns and Incidence of Type 2 Diabetes in US Men and Women: Results from Three Prospective Cohort Studies http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1002039