Harvard Study of 195,000 People Links Fiber From Grains and Fruit to Up to 23% Lower Diabetes Risk

People who eat the most cereal fiber have a 23% lower risk of type 2 diabetes, and those who eat the most fruit fiber an 18% lower risk, according to a Harvard study of 195,222 people published in Diabetes Care on April 1.

Researchers at the Harvard T.H. Chan School of Public Health used three large US cohorts followed for up to 34 years, during which 18,369 people developed type 2 diabetes. Comparing the top fifth of intake with the bottom fifth, total fiber was linked to 12% lower risk, cereal fiber to 23% and fruit fiber to 18%.

Higher intakes of total, cereal and fruit fiber were also linked to healthier blood markers of insulin, fats and inflammation. Fruit fiber went with more of several helpful gut microbes, including Faecalibacterium prausnitzii, and the enzymes they use to make butyric acid, according to the paper.

The authors conclude: "Higher intakes of total, cereal, and fruit fiber are associated with a lower risk of T2D and a more favorable metabolic profile, with the gut microbiome potentially contributing to the beneficial association of fruit fiber."

Only plants contain fiber, so oatmeal, whole wheat bread, brown rice, apples and berries all count.

It's more good news for people managing blood sugar, after a German study linked plant-based eating to a 21% lower risk of death in type 2 diabetes and a whole food plant-based diet was shown to help reverse type 2 diabetes.

Fill up on fiber!