Is Corn Good for Diabetes? An In-Depth Guide
Written by Isabel Vasquez RD, LDN
Corn is a Latine food staple, especially in Mexican, Peruvian, Venezuelan, and Colombian cuisine. It forms the basis for foods like arepas, tortillas, and tamales. With our Latine community facing relatively high rates of diabetes, you may wonder whether corn is part of a healthy diet for diabetes.
In this blog, I’ll share the nutritional value of corn, how it impacts blood sugars, and how you can incorporate corn while managing your diabetes. Let’s get to it!
Corn Nutrition Facts
Corn is commonly mistaken as a vegetable, but it is actually a grain. And not just a grain, but a whole grain!
It is recommended that at least 50% of the grains we consume be whole grains because whole grains have been shown to promote our health by reducing our risk for cardiovascular disease, diabetes, and certain cancers. This is because they are a fully intact grain, containing all three parts: the brain, the germ, and the endosperm.
Refined grains, like white bread or white rice, only contain the endosperm. The bran and germ contain most of the fiber and micronutrients (vitamins and minerals).
Below are the main nutrients in one cup of yellow corn according to the USDA:
Carbohydrates: 31 grams
Protein: 5 grams
Fat: 2 grams
Fiber: 4 grams (14% daily value)
Thiamin: 0.14 milligrams (12% daily value)
Vitamin C: 8.2 milligrams (9% daily value)
Potassium: 325 milligrams (7% daily value)
Niacin: 2.5 milligrams (16% daily value)
Folate: 34 micrograms (8.5% daily value)
As you can see, corn is rich in numerous vitamins and minerals, as well as fiber. It is primarily a source of carbohydrates, but it does contain some protein and fat.
Diabetes in the Latine Community
As I mentioned above, our Latine community is often particularly concerned about type 2 diabetes. According to the American Diabetes Association, as of 2019, 11.8% of Hispanics had a diabetes diagnosis. In contrast, 14.5% of American Indians/Alaskan Natives and 7.4% of non-Hispanic whites had a diagnosis. Within the category of “Hispanic”, we saw the highest rates of diagnosed diabetes amongst Mexican Americans and the lowest rates amongst Cubans.
How Do Carbohydrates Impact Diabetes?
When most people think of nutrition for diabetes care, they probably think of carbohydrates. And that is for a good reason.
Type 2 diabetes happens when your body’s insulin–a hormone released by your pancreas that helps move the sugars you consume from your bloodstream to your cells–doesn’t work as well as it should, so your body excretes more insulin while blood sugar levels rise.
Carbohydrates are broken down into sugars by our bodies, so they cause blood sugars to rise and insulin to be released. Therefore, nutrition management of diabetes typically includes being mindful of carbohydrate consumption and pairing carbohydrate-rich foods with fiber, protein, and fats. Since these other food groups are digested slower by our bodies, they reduce the rate at which blood sugars rise.
Glycemic index
Glycemic index (GI) is a measure of how much a food will raise your blood sugars. It is rated on a scale from 0 to 100, with pure glucose (sugar) scoring 100. There are three categories for the glycemic index of a food:
Low: 55 and below
Medium: 56 to 69
High: 70 and above
The GI of sweet corn is somewhere between 50-55, which would be classified as a low GI.
The issue with only using GI is that it assumes you are eating the food alone and on an empty stomach, which isn’t typically how we eat. Here at Your Latina Nutrition, we’re always talking about how you can add nutrition to your meals, and this is partly why!
Glycemic load
Glycemic load (GL) is a little different from GI in that it also considers the total amount of carbohydrate of a food.
The formula used to calculate GL is:
(glycemic index of the food x grams of carbohydrate) / 100
So, if you were having a 100 grams of yellow corn, you would calculate the GL like this (if we use 55 as the GI):
(21 grams of carbs x 55) / 100 = 11.55
This is because 100 grams of yellow corn contains 21 grams of carbohydrate, and the glycemic index of corn is about 55. So, the GL of this portion of corn would be 11.55.
Similar to GI, there are three categories for the glycemic load of a food:
Low: 10 and below
Medium: 11 to 19
High: 20 and above
So, 100 grams of yellow corn has a medium GL.
As a reminder, GL is largely impacted by the amount you have. Having a smaller portion of corn and pairing it with protein, fat, and non-starchy vegetables would lower the glycemic load of the meal as a whole.
Research on Corn and Diabetes
Whole grains can reduce risk for type 2 diabetes
Remember, corn is a whole grain. There is a lot of research on the health benefits of whole grains, and one finding is that they reduce the risk of type 2 diabetes.
Part of this is because of their fiber content, which helps promote blood sugar management by reducing the rate at which our bodies absorb sugars. Since our bodies can’t digest fiber, it helps mitigate the rapid absorption of simple sugars or refined carbs. Studies have shown that increasing fiber intake can improve glycemic control and reduce risk of premature death.
Some studies even show that higher whole grain and fiber intake is more important than GI or GL in reducing risk for type 2 diabetes.
Whole grains can reduce risk for cardiovascular disease
In addition to reducing the risk of type 2 diabetes, consuming whole grains can reduce the risk of cardiovascular disease. This is relevant because diabetes and heart disease are related. According to the CDC, those with diabetes are twice as likely to have heart disease.
Purple corn may increase insulin secretion and glucose uptake
An in vitro study (meaning it was done in a test tube or petri dish) showed that anthocyanins–naturally occurring colored pigments –in purple corn promoted more insulin secretion in response to glucose intake. It also enhanced cellular uptake of glucose. These are important measures for diabetes management.
However, in vivo research (research done on human beings) is needed to confirm these findings.
Importance of Cultural Foods for Latine Health
Here at Your Latina Nutrition, we’re always advocating for the value of our Latine cultural foods. They nourish us in so many ways–nutritionally, emotionally, and culturally– and oftentimes are central to our identities.
As you can see, corn has a lot of nutritional value to offer. It is a whole grain rich in fiber and packed with vitamins and minerals. So many of our dishes center corn, which we can see enhances their nutritional value. There is no need to fear this cultural food staple! If anything, it should be celebrated!
Sample Meals With Corn For Blood Sugar Management
We’ve talked about how pairing carbs, fiber, protein, and fat is key for blood sugar management. Here are a few sample Latine meals that do that:
Tacos made with corn tortillas, carne asada, guacamole, cotija cheese, and salsa
Arepa filled with shredded pork, peppers, onions, and cheese
Sancocho made with corn on the cob, your favorite meat, and veggies
These are just some general ideas that may not work for everyone. If you’re looking for more support and recommendations for managing your blood sugars, we offer 1:1 nutrition counseling.
Final Thoughts
As you can see, corn can be a great food to incorporate if you have diabetes. It is rich in fiber and micronutrients, and it is a whole grain. These components can even reduce the risk of diabetes and cardiovascular disease.
Since corn is rich in carbohydrates, pairing it with protein and fiber can not only help you manage your blood sugar levels, but help you feel more energized for longer after your meal. This Latine cultural food staple has so much to offer us!
FAQs
Can corn raise blood sugar?
Yes, corn will raise your blood sugar because it contains carbohydrates. However, it has a low glycemic index and is a good source of fiber. Pairing it with foods rich in fiber, protein, and fat can help reduce the rate at which your blood sugars rise and promote blood sugar management.
How much corn can someone with diabetes eat?
There is no one-size-fits-all amount of corn appropriate for someone with diabetes. Each person is different, and their bodies’ response to certain foods will be different. What’s most important is monitoring your unique blood sugars, pairing carbs with protein, fiber, and fat, and noticing how your blood sugars respond.
Keep in mind that it isn’t only food that impacts your blood sugars, but also things like stress, sleep, and physical activity.
Is corn better than rice for diabetes?
While corn and rice are both carbohydrate sources, there are so many varieties of corn and rice with different nutritional profiles. Different varieties may range in their fiber and micronutrient content.
We know that whole grains have a lot of health benefits, but that doesn’t mean that refined grains–like white rice–don't also have a place in a health-promoting eating pattern. Finding the food combinations that both satisfy you and promote your health is key, and that will vary from person to person. Ultimately, incorporating nutritional variety is the most important thing.
Is it better to eat fresh, frozen, or canned corn?
Fresh, frozen, and canned corn have similar nutritional benefits; however, canned corn may have other additives like sodium that you may want to be mindful of if you have certain health conditions like high blood pressure.
Frozen corn is often free from additives, but you can check the ingredients list to be sure.
Canned and frozen corn is way more convenient for most people since it has a longer shelf life and it’s often more affordable. There is nothing wrong with eating these types of corn! It can be an easy way of getting in this nutrient-packed food.
Are corn tortillas better than flour tortillas for diabetes?
Since corn tortillas are made from a whole grain, they have more fiber and micronutrients than regular flour tortillas. Flour tortillas are made with a refined grain (unless they’re whole wheat flour tortillas), so they will typically have less fiber and micronutrients.
Since fiber is beneficial for blood sugar management, corn tortillas are a great option. If you prefer flour tortillas, you can add fiber with foods like salsa, peppers and onions, and avocado.
For education on how to ADD nutrition to your favorite Latine cultural dishes, make peace with food, and focus on your health without dieting, join our nutrition library for just $27/month.
