Despite the popularity of cutting carbs like bread, cereal, and pasta, science continues to support eating whole grains for best health.
A recent study out of Chalmers University of Technology in Sweden and the Danish Cancer Society Research Center finds that no matter what whole grain you eat, it helps to prevent type 2 diabetes (1).
While consumption of whole grains has been indicated in prevention of adult-onset diabetes, the ways in which various whole grains reduce risk and the amount of whole grains to consume in order to reduce diabetes risk has not been studied in much depth yet.
Senior researcher and professor in Food and Health at Chalmers University of Technology, Rikard Landberg, notes that studies similar to his have been done in the USA where the main whole grain consumed is wheat. His team set out to evaluate different cereals as they contain differ fiber and bioactive compounds, which have been found to affect risk factors for type 2 diabetes (1).
The study, which was completed in Denmark, found that it didn’t matter which whole grain product participants consumed -- rye, oats, or muesli -- all offered similar protection from the development of type 2 diabetes. What did make a difference was how much whole grain food a person ate on a daily basis (1).
Subjects were divided into 4 different groups, depending on how many whole grains they reported eating. Subjects that consumed at least 50 grams of whole grains per day were considered "highest consumption."
Those who developed type 2 diabetes reported the lowest intake of whole grains, while men with highest whole grain consumption had a 34% lower risk of diabetes and women had a 22% lower risk.
Landberg notes that it’s uncommon to study a large range of individuals’ whole grain intake. "If you divided American participants into 4 groups, the group that ate the most wholegrain would be the same level as the group that ate the least wholegrain in Denmark. In Europe, Scandinavia eats the most, Spain and Italy the least." The study included 55,000 subjects over a span of 15 years.
Landberg states that whole grain consumption is one of the best ways to cut the risk of type 2 diabetes when compared to other foods that have been studied. Coffee consumption and avoiding red meat are other ways to effectively reduce the risk of type 2 diabetes development (2).
Landberg’s results align with the dietary advice to swap refined grains containing white flour with whole grains. There are additional health benefits to making such a swap, especially when it comes to getting more fiber, vitamins, minerals, and phytochemicals (2).
To be considered a whole grain, a food must contain all three main components of the grain kernel, including endosperm, germ, and bran. Individuals adopting a low-carb diet will not experience the positive benefits of eating whole grains, which come primarily from the bran and germ. Landberg believes cereals and foods containing carbohydrates in general, should not be skipped in the diet, stating,
Carbohydrates are a very varied group of foodstuffs, including sugar, starch, and fibre. We should discuss these more individually, and not throw them together in one group, because they have totally different effects on our physiology and health. When it comes to wholegrains, the research results are clear: among the many studies which have been made, in varied groups of people around the world, there hasn't been a single study which has shown negative health effects.
Whole grains include loose grains such as oats, rice, bulgur and wheatberries or wholegrain flour like rye, wheat, and corn. Cereals containing more whole grains are wheat, rye, oats, corn, millet, sorghum, and maize.
Dietary advice from Sweden includes consuming roughly 70 grams of whole grains daily for women and 90 grams daily for men. Not sure how many whole grains you're getting? Check out this handy list...
- 1 50g slice of rye bread: 16 g whole grains
- 1 35g serving of oatmeal porridge: 35 g whole grains
- 1 12g crispbread: 12 g whole grains
The research utilized data from a prospective Danish cohort study on diet, cancer, and health. It included over 55,000 subjects between the ages of 50-65 years when the study was initiated. At the start of the study in the 1990’s, healthy subjects completed detailed questionnaires about their eating habits. With the use of these, researchers decided subjects’ total whole grain daily intake, common cereals consumed containing whole grains and the total number and various types of whole grain products in grams per day, whether it came from rye bread, whole grain breads, oatmeal, porridge, or muesli.
The study was associated with Denmark’s national diabetes register to study which subjects developed type 2 diabetes over a 15-year period. This study included over 7,000 individuals.
Dietitians can continue to advise whole grains as part of a healthy diet, especially in those at risk for diabetes. Simple tips such as swapping brown rice for white rice, whole grain pasta for white pasta and trying muesli, bulgur, and other whole grains are great ways for clients to boost their whole grain intake.
By Lisa Andrews, MEd, RD, LD
- Cecilie Kyrø, Anne Tjønneland, Kim Overvad, Anja Olsen, Rikard Landberg. Higher Whole-Grain Intake Is Associated with Lower Risk of Type 2 Diabetes among Middle-Aged Men and Women: The Danish Diet, Cancer, and Health Cohort. The Journal of Nutrition, 2018; 148 (9): 1434 DOI: 10.1093/jn/nxy112
- Neal Barnard,, Susan Levin, and Caroline Trapp. Meat consumption as a risk factor for type 2 diabetes. Nutrients. 2014 Feb; 6(2): 897–910.
- Marit Eika Jørgensen, Jette K Kristensen, Gitte Reventlov Husted, Charlotte Cerqueira, and Peter Rossing. The Danish Adult Diabetes Registry. Clin Epidemiol. 2016; 8: 429–434.