Corn is a starchy vegetable and cereal grain that has been eaten all over the world for centuries.
It’s rich in fiber, vitamins and minerals.
However, the health benefits of corn are controversial — while it contains beneficial nutrients, it can also spike blood sugar levels. In addition, the crop is often genetically modified.
This article looks at the possible benefits and disadvantages of eating corn.
Corn is considered both a vegetable and a cereal grain.
Sweet corn that you eat off the cob is usually considered a vegetable in the culinary world, whereas the dry seeds that are used for popcorn are classified as whole grains.
Corn originated in Mexico over 9,000 years ago and is known by its original name “maize” in many parts of the world. Native Americans grew and harvested this crop as a main source of food (, ).
Today, it’s one of the most widely consumed cereal grains worldwide (3).
Corn is usually white or yellow but also comes in red, purple and blue.
It’s eaten as sweet corn, popcorn, tortillas, polenta, chips, cornmeal, grits, oil and syrup and added to countless other foods and dishes.
What’s more, it’s widely used for fuel and animal feed. In fact, 40% of the corn grown in the US is used for fuel and 60–70% of corn worldwide is produced to feed animals (, ).
Summary Corn is a popular food that is considered both a vegetable and whole grain. It can be eaten whole as sweet corn or popcorn or processed into chips, oil and syrup. However, most corn is used for animal feed and fuel production.
Corn is high in carbs and packed with fiber, vitamins and minerals. It’s also relatively low in protein and fat.
One cup (164 grams) of sweet yellow corn contains (5):
- Calories: 177 calories
- Carbs: 41 grams
- Protein: 5.4 grams
- Fat: 2.1 grams
- Fiber: 4.6 grams
- Vitamin C: 17% of the daily value (DV)
- Thiamine (vitamin B1): 24% of the DV
- Folate (vitamin B9): 19% of the DV
- Magnesium: 11% of the DV
- Potassium: 10% of the DV
Most of the carbs in corn come from starch — which can quickly raise your blood sugar, depending on how much you eat. However, it’s also high in fiber that can help balance your blood sugar levels (3, 6).
Due to its impressive nutrient profile, most people can benefit from eating whole corn and popcorn as part of a balanced diet. It’s also a naturally gluten-free food and can be eaten by those who avoid gluten.
On the other hand, processed corn products may not be very nutritious, as refined oil, syrup and chips lose beneficial fiber and other nutrients during production. Also, many processed products are high in added salt, sugar or fat (7, 8).
Summary Whole corn is loaded with fiber and contains vitamin C, B vitamins, magnesium and potassium. Processed corn products are not as nutritious.
Corn contains antioxidants and plant compounds that may provide a number of health benefits.
Lutein and Zeaxanthin Content May Benefit Eye Health
Corn is particularly high in lutein and zeaxanthin, two carotenoids that may prevent cataracts and age-related macular degeneration (AMD).
This is likely because lutein and zeaxanthin make up a large part of the macular region of your eyes (, , ).
One study in 365 adults found that those who had the highest intake of carotenoids — especially lutein and zeaxanthin — had a 43% lower chance of developing AMD compared to those with the lowest intake ().
Therefore, regularly eating corn may promote eye health — especially for those who are at risk of AMD.
May Prevent Diverticular Disease and Other Digestive Issues
The fiber in corn may also provide health benefits.
Dietary fiber intake has been linked to a lower risk of several diseases, including heart disease and some cancers. Even more, eating enough fiber promotes healthy digestion and may protect you against gut issues (, , ).
Corn, in particular, may protect against specific digestive issues, including diverticular disease, which is characterized by inflammation of the digestive tract ().
One 18-year study in over 47,000 adult men associated eating popcorn at least twice a week with a significantly lower risk of diverticular disease ().
Based on these limited results, eating corn and popcorn may promote gut health and prevent digestive diseases. However, more research is needed.
Summary Corn is loaded with plant compounds that are linked to a lower risk of eye diseases. Even more, the fiber in corn may provide a number of health benefits and reduce your risk of diverticular disease.
Since corn is high in starch, it can spike your blood sugar and may not be suitable for some populations.
People who have diabetes may need to limit their starchy carb intake, including corn.
Research specifically focusing on corn intake and diabetes is limited, but studies suggest that low-carb diets are more effective at managing diabetes ().
A study in 115 adults with obesity and type 2 diabetes found that eating a diet with only 14% of calories coming from carbs resulted in more stable blood sugars and a reduced medication need compared to getting 53% of the daily calories from carbs ().
Eating less of other corn products, especially high-fructose corn syrup, may help prevent diabetes.
One study found that the prevalence of diabetes was 20% higher in countries with easier access to high-fructose corn syrup, compared to areas where the syrup was not readily available ().
Finally, people who are trying to lose weight may want to limit their intake of starchy carbs from corn.
A 24-year Harvard study in 133,468 adults found that each additional daily serving of corn was associated with a 2-pound (0.9-kg) weight gain per 4-year interval. Potatoes, peas and other starchy vegetables did not contribute to as much weight gain ().
Summary Corn can spike your blood sugar and may contribute to weight gain when consumed in excess. Individuals who have diabetes or are trying to lose weight may want to limit their intake.
Corn is one of the most genetically modified crops in the world. In fact, 92% of the crop grown in the US in 2016 was genetically modified (GMO) (19).
Corn crops are modified to increase yield and improve resistance to insects, disease or chemicals used to kill pests (19).
The impact of modified corn and other crops on human health and environmental safety is one of the most widely debated topics in the field of nutrition.
Current research on the safety of genetically modified corn for humans is limited and conflicting.
For one, studies have linked consumption of genetically modified corn with toxic effects on the liver, kidneys and other organs in animals (, ).
On the other hand, some research suggests that modified crops are not harmful to human health and provide the same nutrients as non-modified crops.
One study found no significant differences between the content of vitamin C, certain minerals, fatty acids, antioxidants and other beneficial nutrients in genetically modified corn compared to corn crops that were not modified ().
More research is needed to help consumers make an informed decision about eating genetically modified corn. If you’re concerned about eating genetically modified crops, look for products that have a “non-GMO” label.
Summary Most corn has been genetically modified. While more research is needed, some studies suggest that modified crops may pose health risks to humans.
Corn is a versatile food that can be added to your diet in many ways.
Sweet corn and corn on the cob are widely available at grocery stores and farmers markets in both fresh, frozen and canned varieties.
Fresh cobs can be prepared by heating them over a grill or by cooking them in boiling water. They’re usually served with melted butter and salt.
Kernels can be added to soups, salads, vegetable dishes or served on their own with butter or olive oil and seasonings.
Other varieties of corn, such as flour and dried kernels, can also be used. You can make tortillas with finely ground corn flour, water and salt. These can be turned into homemade chips by baking sliced pieces with oil and seasonings.
Finally, dried kernels can be used to make popcorn on your stove or in an air popper for a delicious and satisfying snack.
Summary Corn on the cob, corn kernels, corn flour and popping corn are widely available at grocery stores and can be used in a variety of dishes.
Corn is rich in fiber and plant compounds that may aid digestive and eye health.
Yet, it’s high in starch, can spike blood sugar and may prevent weight loss when consumed in excess. The safety of genetically modified corn may also be a concern.
Still, in moderation, corn can be part of a healthy diet.