Do All Plant-Based Diets Effectively Reduce Diabetes Risk?

Adhering to a healthy vegetarian diet significantly reduces the risk of developing type 2 diabetes, according to recent research.

While plant-based diets have been recommended for the reduction in risk of type 2 diabetes, not all plant foods are necessarily healthful.

To assess which plant-based options are best for the reduction of diabetes risk, researchers examined data from 3 prospective cohort studies including 69,949 women from the Nurses’ Health Study (1984–2012), 90,239 women from the Nurses’ Health Study 2 (1991–2011), and 40,539 men from the Health Professionals Follow-Up Study (1986–2010).
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Using dietary data, the researchers created a plant-based diet index (PDI), on which plant-based foods were given high scores and animal-based options were given lower scores. They also created a healthful PDI (hPDI) and an unhealthful PDI (uPDI), with which healthy and unhealthy plant- and animal-based foods were ranked. Unhealthy plant-based foods included fruit juices, refined grains, and potatoes.

The researchers observed 16,162 cases of type 2 diabetes during follow-up. Overall, both PDI and hPDI were inversely associated with diabetes risk. The association between diabetes and PDI was considerably attenuated after adjusting for body mass index categories, while that of HPDI remained relatively unchanged. uPDI was positively associated with diabetes risk even after adjustment.

“We found an inverse association between an overall plant-based diet and [diabetes] incidence in 3 prospective cohorts,” the authors wrote. “This inverse association was stronger for an index that captured a healthier version of the plant-based diet, but the association with [diabetes] was positive for an index that captured an unhealthful version of a plant-based diet. Our study supports current recommendations to shift to diets rich in healthy plant foods, with lower intake of less healthy plant and animal foods.”

—Michael Potts

Reference:
Satija A, Bhupathiraju SN, Rimm EB, et al. Plant-based dietary patterns and incidence of type 2 diabetes in us men and women: results from three prospective cohort studies [published online June 14, 2016]. doi:10.1371/journal.pmed.1002039.