Eating more fruits, vegetables, and whole grains is associated with a lower risk of developing type 2 diabetes, according to two published studies. BMJ Today.
The results suggest that a small increase in consumption of these foods as part of a healthy diet may help prevent type 2 diabetes.
In the first study, a team of European researchers examined the relationship between blood levels of vitamin C and carotenoids (pigments found in colorful fruits and vegetables) and the risk of developing type 2 diabetes.
Vitamin C and carotenoid levels are more reliable indicators of fruit and vegetable intake than using dietary questionnaires.
Their results are based on 9,754 adults who developed new-onset type 2 diabetes and a comparison group of 13,662 adults who were free of diabetes during follow-up with 340,234 participants participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) in eight European countries. Study.
After adjusting for lifestyle, social and dietary risk factors for diabetes, higher blood levels of each of vitamin C and carotenoids and their sum combined into a “composite biomarker score” reduced the risk of developing type 2 diabetes.
Compared to people who had the lowest composite biomarker scores, those with biomarker scores in the top 20% of the population had a 50% lower risk. Biomarker scores between these two extremes included those with intermediate risk.
The researchers calculated that an increase in total fruit and vegetable intake of 66 grams per day was associated with a 25% lower risk of developing type 2 diabetes.
In the second study, researchers in the United States examined the relationship between total and individual whole grain dietary intake and type 2 diabetes.
Their results are based on 158,259 women and 36,525 men who were free of diabetes, heart disease, and cancer and were participating in the Nurses’ Health Study, the Nurses’ Health Study II, and the Health Professionals Follow-Up Study.
After adjusting for lifestyle and dietary risk factors for diabetes, participants in the highest category for whole grain consumption had a 29% lower rate of type 2 diabetes than in the lowest category.
For individual whole-grain foods, the researchers found that eating one or more servings of whole-grain cold breakfast cereal or dark bread a day was associated with a lower risk of type 2 diabetes (19% and 21%, respectively) than eating less than one. Serves one month.
For other individual whole grains with lower average intake levels, eating two or more servings a week was associated with a 21% lower risk for oatmeal than one serving a month, a 15% lower risk for added bran, and a 12% lower risk for brown rice and wheat germ. % Low risk.
These reductions in risk appeared to plateau at about two servings a day for total whole grain intake and about half a serving a day for whole grain cold breakfast cereals and dark bread.
Both studies are observational so cannot establish causation, and some results may be due to unmeasured (confounding) factors. However, both studies took into account several well-known lifestyle risk factors and markers of dietary quality, and the results back up other studies linking a healthy diet to better health.
As such, both research teams say their findings provide further support for current recommendations to increase fruit, vegetable and whole grain consumption as part of a healthy diet to prevent type 2 diabetes.
And for fruits and vegetables, findings also suggest that consuming even a moderately increased amount can help prevent type 2 diabetes in populations that typically consume low amounts.