You just can’t ignore the fact that fruit, vegetables and grains are good for you.

The latest reminder comes from two studies in the same edition of the British Medical Journal showing that even a modest increase in consumption is associated with a lower risk of developing type 2 diabetes.

In the first study, a European team examined the blood levels of vitamin C and carotenoids (pigments found in colourful fruits and vegetables) in 9754 adults who developed new-onset type 2 diabetes and a comparison group of 13,662 who didn’t. All were participants in the European Prospective Investigation into Cancer and Nutrition (EPIC).

Vitamin C and carotenoid levels are considered more reliable indicators of fruit and vegetable intake than dietary questionnaires.

After adjusting for lifestyle, social and dietary risk factors for diabetes, higher blood levels of each individually and combined were found to be associated with a lower risk of developing type 2 diabetes.

The researchers suggest it could be as much as 25% lower for every 66 grams per day increase in total fruit and vegetable intake.

The work was led by the University of Cambridge, and involved researchers from the UK, Norway, the Netherlands, Sweden, Spain, Germany, France, Italy, Denmark and Luxembourg.

In the second study, researchers in the US, led by the Harvard TH Chan School of Public Health, examined associations between total and individual whole grain food intake and type 2 diabetes risk, working with 158,259 women and 36,525 men who were free from diabetes, heart disease and cancer.

After adjusting for lifestyle and dietary risk factors for diabetes, participants in the highest category for total whole grain consumption had a 29% lower rate of type 2 diabetes compared with those in the lowest category.

Consuming one or more servings a day of whole grain cold breakfast cereal or dark bread was associated with a 19% and 21% lower risk respectively than consuming less than one serving a month.

Consuming just two servings a week was associated with a 21% lower risk for oatmeal, a 15% lower risk for added bran, and a 12% lower risk for brown rice and wheat germ.

These reductions in risk seemed to plateau at around two servings a day for total whole grain intake, the researchers say, and at around half a serving a day for whole grain cold breakfast cereal and dark bread.

Both studies are observational so can’t establish cause, and there’s a possibility that some of the results may be due to unmeasured (confounding) factors.