There is nothing as delicious as a well-buttered cob of corn just off the grill. For many of us, a movie experience is incomplete without a tub of popcorn. Be it soups, salads, or casseroles; corn is an integral part of our diet. But the question that continues to fox many of us is – What is corn? Is it a vegetable, fruit, or grain? Read on to know the answer.
Why is corn a fruit?
The fruit is a seed-bearing structure of a plant that is formed from the ovary of the plant. It encloses seeds. In a typical fruit like apple, the fleshy part of the apple surrounds the seeds. In the case of corn, each kernel is a dry fruit where the ovary wall and the seed are fused into one layer. So, in the strictest scientific sense, corn is a fruit.
Why is corn a grain?
The corn kernel is considered to be a whole grain. A grain is defined as a seed or a fruit of the cereal grass. Corn, wheat, rice, oats, and barley belong to the same family of cereal grasses. This is the reason why popcorn is described as a whole-grain. When you eat the popcorn, you eat the whole kernel with all its parts.
Why is corn a vegetable?
While corn is technically not a vegetable, the USDA Dietary guidelines of Americans list corn both as a starchy vegetable and grain. At most grocery stores, also you will find fresh corn in the vegetable section.
Going by the above definitions, we can safely call corn a fruit, grain, and a vegetable. No matter what you call it or in what form you eat the corn, it is highly nutritious and healthy. It contains specific B vitamins, vitamin C, magnesium, and potassium. Yellow corn also contains antioxidants like zeaxanthin and lutein, which a great for eye health.
Nutrition facts of corn
A 100 grams serving of boiled yellow corn contains (1) –
- Calories – 96
- Water – 73%
- Proteins – 3.4 grams
- Carbs – 21 grams
- Sugar – 4.5 grams
- Fiber – 2.4 grams
- Fat – 1.5 grams
Starch is the primary carb in corn; it comprises 28 to 80 percent of its dry weight. Corn also provides a small amount of sugar. Sweet corn is higher in sugar content (18%). Despite the high sugar content, sweet corn is not a high-glycemic food.
The protein content of corn can range from 10 to 15 percent. Almost 44 to 79% of the total protein content of corn is zeins. Zeins are inferior quality proteins because they do not contain some essential amino acids. They are used for the production of adhesives, inks, and coating for pills and candy.
Corn is a low-fat food with just 5 to 10% fat content. Refined corn oil is made of linoleic acid, a polyunsaturated fatty acid.
Vitamins and minerals
While sweet corn is high in many vitamins, popcorn is rich in minerals. Popcorn contains several minerals like manganese magnesium, phosphorus, copper, and zinc. Sweet corn contains vitamin B5, B6, B9(folic acid), B3, and potassium.
Corn also contains several other plant compounds that help boost health. It contains anthocyanins, zeaxanthin, lutein, ferulic acid, and phytic acid.
1. Improves eye health
Carotenoids like lutein and zeaxanthin are essential for boosting eye health. These two carotenoids account for 70 percent of the total carotenoid content of corns (2). Commonly known as the macular pigments, these compounds exist in the retina, and they protect the eyes from damage caused by the blue light (3).
A study of 356 patients with age-related macular degeneration showed a 43% lower risk of macular degeneration in patients that took the highest intake of carotenoids like lutein and zeaxanthin (4).
2. Improves digestion
One cup of corn provides 18.4 percent of the daily need for dietary fiber. This helps in lowering problems like constipation and hemorrhoids and also helps in reducing the risk of colon cancer (5). Dietary fiber helps to bulk up and soften the stools, which reduces the risk of irritable bowel syndrome and diarrhea as well.
Corn also helps in preventing diverticulosis. This condition is characterized by pouches on the wall of the colon. It causes symptoms like bloating, flatulence, cramps, bleeding, and infection. According to a study by the University of Washington School of Medicine, men who eat popcorn are 28% less likely to develop the diverticular disease (6).
3. Rich in protective antioxidants
Corn is rich in several antioxidants which are beneficial for health. Lutein and zeaxanthin help prevent macular degeneration and cataracts. The quercetin in corn helps to combat acute and chronic inflammation and protects against neurodegenerative diseases like Alzheimer’s. Quercetin has also been linked to apoptosis, the process that allows the body to kill of dysfunctional cells.
4. Prevents anemia
Corn is rich in iron, which is needed by our body to form new red blood cells. A deficiency in iron can lead to anemia. Corn also contains vitamin A and beta carotene, which increase the absorption of iron.
5. Lowers the risk of diabetes
Corn has one of the highest levels of polyphenol-antioxidants in fruits and vegetables that are considered beneficial in preventing type-2 diabetes. Three cups of popped corn have twice the amount of polyphenols as compared to a typical serving of fruit. A moderate intake of resistant starch can reduce glucose and insulin response. Opt for air-popped corn and avoid microwaved popcorn.
6. Soothes skin rashes and irritation
Corn is highly beneficial in maintaining youthful looks and preventing aging. A regular massage with corn oil improves skin texture. Since corn starch is rich in vitamin E, it helps to remove facial acne scars.
7. Beneficial during pregnancy
Moderate consumption of sweet corn can be helpful during pregnancy. It helps to address problems like constipation, which many women experience during early pregnancy.
Corn also contains folic acid, which is necessary during pregnancy to prevent congenital disabilities like spina bifida during pregnancy. Thiamine in corn plays a vital role in energy metabolism and is essential for muscle and nervous system functioning.
Adverse effects of eating corn
Corn is generally safe to eat. However, it can have some negative impacts on health.
1. Phytic acid
Corn contains phytic acid, which can impair the absorption of dietary minerals. Soaking, sprouting, or fermenting corn can help reduce the effects of phytic acid.
2. Contamination by fungi
Like many other cereal grains, corn is susceptible to contamination by fungi. Fungi produce toxins known as mycotoxins, which can cause health concerns. Fumonisins, aflatoxins, and trichothecenes are the main classes of mycotoxins in corn. High consumption of contaminated corn can increase the risk of cancer and neural tube defects.
3. Corn intolerance
Corn also contains zein, which are proteins related to gluten. Zein can cause inflammation in some people with celiac disease. Corn is also known to trigger symptoms in some people with IBS or FODMAP intolerance.
Ways to prepare and eat corn
Many people prefer to eat corn after cooking it and flavoring it with butter, oil, and seasonings. You can also eat young and tender corn raw. Here are some tips to prepare and store corn –
- You can store uncooked corn in the refrigerator for five days.
- You can freeze corn at zero degrees F for six months.
- Corn can be roasted, boiled, steamed, grilled, or microwaved.
- You can add it to salads, salsa, stew, or casseroles.
- Once the corn is cooked, it can stay good for three to five days in the refrigerator.
The history and origins
Corn does not exist naturally in the world. It was developed and cultivated by the people living in central Mexico 7000 years ago. It started from a grass called teosinte. The kernels of this corn were small and not as well placed as the corn we eat now. The Indians throughout North and South America depended on corm (also known as maize) for their food.
From Mexico, the cultivation of maize spread to the southwest US and the coast of Peru. When the Indians migrated to the eastern woodlands of present-day North America 1000 years ago, they brought corn with them.
Europeans, like Columbus, introduced corn to Europe. Today there are many different kinds of corn available. These include –
Flint corn – It is also known as the Indian corn and has kernels that range from white to red. It is grown in Central and South America. Popcorn is a kind of flint corn.
Dent Corn – It is also known as field corn and is used to feed livestock. It has white or red kernels. It is also used for making industrial products.
Sweet corn – It can be eaten on the cob or can be canned or frozen. It contains more sugar than all other types of corn.
Corn is a vegetable, fruit, and grain. It is highly nutritious and provides many health benefits. It improves eye health, boosts digestion, prevents anemia, is beneficial during pregnancy, and also improves skin. Corn can be roasted, boiled, steamed, grilled, or microwaved. You can add it to salads, salsa, stew, or casseroles.