Corn is a nutritious cereal and a supply of fiber, vitamins, minerals, and antioxidants. It can support eye and digestive well-being. Highly processed corn products, however, like tortilla chips, provide fewer nutritional advantages.
Also termed maize (Zea mays), corn ranks among the world’s most consumed cereal grains. It’s the seed of a grass-family plant, originating in Central America but cultivated in numerous varieties across the globe.
Popular types include popcorn and sweet corn, while refined corn derivatives are broadly consumed, often as components of processed foods.
These derivatives encompass tortillas, tortilla chips, polenta, cornmeal, corn flour, corn syrup, and corn oil.
Whole-grain corn is more nutrient-dense, being high in fiber and supplying a variety of vitamins, minerals, and antioxidants.
Although commonly yellow, corn is available in several other hues, such as red, orange, purple, blue, white, and black.
This article covers what you need to know about corn.
Nutrition facts
Below are the nutrition details for 3.5 ounces of boiled yellow corn:
- Calories: 96
- Water: 73%
- Protein: 3.4 grams
- Carbs: 21 grams
- Sugar: 4.5 grams
- Fiber: 2.4 grams
- Fat: 1.5 grams
Carbs
Like other cereal grains, corn is largely made up of carbohydrates.
Starch is the predominant carbohydrate, making up about 75% of its dry mass. Corn also supplies small quantities of sugars.
Sweet corn, sometimes called sugar corn, is a low-starch variety with elevated sugar levels. Most of that sugar is sucrose.
Despite sweet corn’s sugar, it is not a high-glycemic food, placing low to medium on the glycemic index (GI).
The GI gauges how rapidly carbohydrates are digested. Foods ranking high can trigger rapid spikes in blood glucose.
Fiber
Corn delivers a reasonable amount of fiber.
Three cups of air-popped popcorn provide roughly of fiber. This corresponds to 13% of the .
The dominant fibers in corn are insoluble types, like hemicellulose, cellulose, and lignin.
Protein
Corn supplies modest amounts of protein.
Depending on the cultivar, protein content varies from to .
The most prevalent proteins in corn are termed zeins, representing 40–50% of total protein.
Overall, zeins are of low protein quality because they lack certain essential amino acids.
Zeins also have numerous industrial uses, such as in producing adhesives, inks, and coatings for pharmaceuticals, confections, and nuts.
Corn oil
Corn’s fat content ranges from to , making the grain relatively low in fat.
However, corn germ — a plentiful by-product of milling — is high in fat and is processed into corn oil, a common cooking oil.
Refined corn oil is primarily linoleic acid, a polyunsaturated fatty acid, while monounsaturated and saturated fats comprise the remainder.
It also contains vitamin E and notable amounts of phytosterols, which extend shelf life and may help lower cholesterol.
Vitamins and minerals
Corn can provide a fair supply of several vitamins and minerals. Importantly, amounts vary considerably by corn type.
Generally, popcorn is , while sweet corn contains higher levels of many vitamins.
Popcorn
This well-liked snack contains several vitamins and minerals, such as:
- Manganese. An essential trace element found abundantly in whole grains, legumes, fruits, and vegetables. Its absorption from corn is limited because of the vegetable’s phytic acid content.
- Phosphorus. Present in moderate quantities in both popcorn and sweet corn, phosphorus plays a vital role in the growth and upkeep of body tissues.
- Magnesium. Low levels of this critical mineral may raise your risk of several chronic diseases, including heart disease.
- Zinc. This trace mineral has numerous essential roles; however, its absorption from corn may be limited by phytic acid.
- Copper. An antioxidant trace element that is often low in Western diets. It is an important factor in preventing or slowing age-related macular degeneration (AMD).
Sweet corn
Sweet corn offers several vitamins, including:
- Pantothenic acid. Also known as vitamin B5, this nutrient appears to some degree in nearly all foods; deficiency is rare.
- Folate. Also called vitamin B9 or folic acid, folate is vital, especially during pregnancy.
- Vitamin B6. A group of related vitamins, with pyridoxine being the most common; it performs various bodily functions.
- Niacin. Also referred to as vitamin B3, niacin in corn is not easily absorbed. Treating corn with an alkaline solution like limewater (calcium hydroxide) during cooking can make this nutrient more bioavailable.
- Potassium. An essential mineral important for blood pressure regulation and beneficial for heart health.
Other plant compounds
Corn contains various bioactive plant compounds, some of which may offer health advantages.
In fact, corn of antioxidants than many other common cereal grains:
- Ferulic acid. One of the primary polyphenol antioxidants in corn, which is found in higher amounts than in grains like wheat, oats, and rice.
- Anthocyanins. A family of antioxidant pigments responsible for the color in blue, purple, and red corn varieties.
- Zeaxanthin. Named from corn’s scientific name (Zea mays), zeaxanthin is a common plant carotenoid. In humans, it has been associated with better eye health.
- Lutein. A major carotenoid in corn that acts as an antioxidant, helping protect the eyes from oxidative damage caused by blue light.
- Phytic acid. This compound can reduce absorption of dietary minerals like zinc and iron.
Popcorn
Popcorn is a distinct type of corn that “pops” when heated.
This occurs when water trapped inside the kernel turns to steam, building internal pressure that causes the kernel to explode.
A widely enjoyed snack, popcorn is one of the most commonly eaten whole-grain foods in the United States.
It’s also among the few whole grains consumed alone as a snack; more often, whole grains are eaten as ingredients in foods like bread and tortillas.
Whole-grain foods may offer several health benefits, including a lower risk of heart disease and type 2 diabetes.
However, frequent popcorn consumption has been associated with a higher risk of heart disease.
Although popcorn can be healthy when plain, it is often consumed with sugary soft drinks and commonly coated with extra salt and high-calorie cooking oils, all of which can negatively affect health over time.
You can avoid added fats by using an air popper to make your popcorn.
Health benefits
Consistent consumption of whole grains may provide a range of health benefits.
Eye health
Macular degeneration and cataracts are the most frequent visual disorders and leading causes of blindness.
Infections and aging are key contributors to these conditions, but diet can also play a crucial role.
Dietary antioxidants, especially carotenoids like zeaxanthin and lutein, may support eye health.
Lutein and zeaxanthin are the primary carotenoids in corn, particularly in yellow and orange varieties. Their concentrations are typically lower in white corn.
Known as macular pigments, these compounds are present in the retina — the light-sensitive inner layer of the eye — where they shield against oxidative stress from blue light.
Elevated blood levels of these carotenoids are strongly associated with a reduced risk of macular degeneration and cataracts.
Observational research also indicates that high dietary intake of lutein and zeaxanthin may be protective, although not all studies confirm this.
Prevention of diverticular disease
Diverticular disease (diverticulosis) involves pouch-like protrusions in the colon wall. Typical symptoms include cramps, gas, bloating, and less commonly, bleeding and infection.
Popcorn and other fiber-rich foods were once thought to provoke this condition.
However, an 18-year study of 47,228 men suggests popcorn may actually help prevent diverticular disease. Men with the highest popcorn intake were 28% less likely to develop it compared with those with the lowest intake.
Potential downsides
Corn is generally safe to eat, but there are some concerns to consider.
Antinutrients in corn
Like other cereal grains, whole-grain corn contains phytic acid (phytate).
Phytic acid can hinder absorption of dietary minerals, such as iron and zinc, from the same meal.
While this is usually not problematic for people with balanced diets, it can be a significant issue in developing regions where grains and legumes are dietary staples. Techniques like soaking, sprouting, and fermenting corn can markedly lower phytic acid levels.
Note that phytic acid is mainly a concern when eaten in large quantities, uncooked, and without food variety. Additionally, phytic acid has several health benefits that are often overlooked.
Mycotoxins
Some cereal grains and legumes can be contaminated by fungi.
Fungi produce various toxins, called mycotoxins, which pose significant health risks.
The principal mycotoxin groups in corn are fumonisins, aflatoxins, and trichothecenes. Fumonisins are particularly notable.
They are found in stored cereals worldwide, but harmful effects have predominantly been linked to consumption of corn and corn products — especially among populations that rely on corn as a primary food source.
High intake of contaminated corn is suspected to increase risk of cancer and neural tube defects, congenital anomalies that may cause disability or death.
Other mycotoxins can also have detrimental effects. In April 2004, 125 people died in Kenya from aflatoxin poisoning after consuming improperly stored homegrown corn.
A 2023 study of corn cultivated in Iowa during a drought year found that extreme weather raises the risk of fungal contamination.
Prevention strategies include fungicide use and proper drying methods.
In most developed nations, food safety authorities monitor mycotoxin levels in marketed foods, and production and storage practices are tightly regulated.
The bottom line
Corn is among the most commonly eaten cereal grains worldwide.
As a good source of antioxidant carotenoids like lutein and zeaxanthin, yellow corn may support eye health. It also supplies a variety of vitamins and minerals.
Accordingly, moderate consumption of whole-grain corn, such as popcorn or sweet corn, can be a valuable part of a healthy eating pattern.
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