These days, even in mainstream markets, you can find spelt, millet, barley, and the like. And the marketing messages leaping off of every loaf of bread and cereal box shout, “whole grains!” Additionally, every healthy-eating article has authors singing the praises of whole grains, citing all kinds of studies showing that eating these wonder foods will reduce your risk of heart disease, cancer, and more.
However, the research supporting the benefits of these popular foods isn’t as strong as you might think. And there’s another side to whole grains that’s important to keep in mind if you have diabetes: They can significantly raise blood sugar.
A 2013 study of people with type 2 diabetes found that most whole-grain breads raised blood sugar and insulin levels just as much as bread made from refined white flour. The exception was pumpernickel, which increased blood sugar less than other types, but caused it to remain above the healthy 140 mg/dL range.
Many observational studies have shown a decreased risk of diabetes, heart disease, and other serious health conditions in people who eat whole grains regularly. However, this only demonstrates a link between whole grain consumption and disease risk reduction. People who eat a lot of whole grains tend to have healthier eating and lifestyle habits overall. They typically consume very little junk food, and engage in regular exercise more often than those who never eat whole grains.
Better Sources of Fiber
Though it’s true that whole grains can be a good source of fiber, there are many other fiber-rich foods that have less of an impact on blood sugar. In fact, whole grains aren’t even that high in fiber when compared with other, lower-carb foods. For instance, a cup of instant oatmeal contains 29 grams of carbs and only 4 grams of fiber. Two slices of whole wheat bread contain 28 grams of carbs and only 4 grams of fiber. On the other hand, check out these great, lower-carb fiber foods:
- Avocado (1/2 medium): 9 grams total carbs, 7 grams fiber
- Artichoke (1 medium): 14 grams total carbs, 10 grams fiber
- Broccoli (1 cup, cooked): 11 grams total carbs, 5 grams fiber
- Lentils (1/2 cup, cooked): 20 grams total carbs, 8 grams fiber
- Blackberries (1 cup): 15 grams total carbs, 8 grams fiber
- Raspberries (1 cup): 15 grams total carbs, 8 grams fiber
- Flaxseed, ground (2 tablespoons): 4 grams total carbs, 3.5 grams fiber
- Chia seeds (2 tablespoons): 12 grams total carbs, 10 grams fiber
- Almonds (¼ cup): 6 grams total carbs, 3.5 grams fiber
Moreover, whole grains don’t contain any specific vitamins or minerals that can’t be found in unprocessed foods that contain fewer carbs. If you eat a variety of other plants but avoid whole-grain products, you can still get all of the micronutrients, antioxidants, and other compounds needed to help maintain good health and reduce disease risk.
However, some people may find it difficult to imagine life without bread, cereal, and other whole grains. If this is true for you, it may be a good idea to conduct an experiment to see how your blood sugar responds to different types and amounts of whole grains. You may be able to handle a slice of bread or small serving of brown rice or oatmeal without experiencing a significant increase in blood sugar. On the other hand, you may be surprised at how much even a small amount of whole grains affects your blood sugar.
Whole grains certainly have an edge over refined grains, because they contain more fiber and nutrients. However, in people with diabetes, these benefits may not be enough to offset their effects on blood sugar. At the end of the day, whether or not to consume whole grains is a personal choice, but they clearly aren’t necessary for good health.
Breen, Cathy, Miriam Ryan, Michael J. Gibney, Michelle Corrigan, and Donal O’Shea. “Glycemic, Insulinemic, and Appetite Responses of Patients With Type 2 Diabetes to Commonly Consumed Breads.” The Diabetes Educator. March 12, 2013.
Kyrø, C., G. Skeie, L.O. Dragsted, J. Christensen, K. Overvad, G. Hallmans, I. Johansson, et al. “Intake of Whole Grains in Scandinavia is Associated with Healthy Lifestyle, Socio-economic and Dietary Factors.” Public Health Nutrition. October 14, 2011.
Reviewed by Franziska Spritzler, RD, CDE