The internet is full of conflicting advice about corn. Some alternative health sites focus on the perceived harms of genetically-modified organism (GMO) corn or they dismiss corn as a potentially dangerous grain. Corn proponents, however, insist that corn forms a core part of a healthful diet.
Corn is in everything from soda to cereal. According to the Tufts University Health & Nutrition Letter, Americans consume about 160 pounds of corn per person each year. This consumption has raised concerns about whether corn is replacing more healthful foods.
Similarly to most foods, corn is neither a cure-all nor a poison. In moderation, it can form a healthful part of most people's diets.
In this article, we explore the nutritional content and potential health benefits of corn. We also discuss risks, health myths, and some tips for eating and preparing corn.
Corn contains fiber and protein but is low in vitamins and minerals.
Today's corn is much different from the corn that the indigenous peoples of North America once grew. Through selective breeding, farmers have steadily domesticated corn, changing its size, color, and flavor in the process.
Most people think of corn as sweet yellow corn, a large form of maize. According to the United States Department of Agriculture (USDA), a 90-gram (g) ear of fresh corn contains:
Compared to many other fruits and vegetables, corn is low in vitamins and minerals. A 90-gram (g) ear of fresh corn contains:
- 4 percent of the recommended daily intake (RDI) of vitamin A
- 6 percent of the RDI for vitamin C
- 2 percent of the RDI for iron
- 0 percent of the RDI for calcium
Many nutrition advocates have expressed concern about corn's high proportion of carbohydrates compared to its low concentration of vitamins and minerals. Carbohydrates are filling, so they argue that corn may replace more nutritionally dense foods.
Studies of diets that exclude corn, such as paleo and ketogenic diets, contain too many variables to isolate the benefits of corn avoidance. However, there is little other evidence to suggest that eating corn is harmful, especially in its organic, ancient form. In moderation, corn can still be a part of a healthful diet.
Corn offers several potential health benefits. These include:
Producers can grow corn easily and quickly in many different regions of the world. Hybridization and domestication have made corn even easier to grow, making corn an affordable commodity.
For people with very low incomes, especially those living in developing nations, corn is a cheap and ready source of calories, carbohydrates, and protein.
Antioxidants combat the effects of harmful free radicals in the body. Research suggests that free radicals may play a role in the aging process and the development of a number of chronic diseases.
Many fruits and vegetables, including dark leafy greens, carrots, and sweet potatoes, are also rich in carotenoids.
Compared with other vegetables, corn is low in nutrients.
Corn, similarly to many grains, legumes, and vegetables, contains dietary fiber.
However, the amount of fiber in corn is often lower than that from other sources. For instance, a half cup of cooked navy beans provides 9.6 g of fiber, while a half cup of cooked corn provides only 2.1 g.
Fiber can help with digestion and reduce the risk of constipation. Some research also suggests fiber may help people live longer. A large 2011 study found a correlation between dietary fiber intake and a lower overall risk of premature death, especially from cardiovascular, infectious, and respiratory diseases.
High in protein
Corn is higher in protein than many other vegetables, making it a good choice for vegetarians and vegans, or for people hoping to eat more protein from nonanimal sources.
Some studies also suggest that a diet rich in protein may support healthful weight loss by either reducing hunger or helping the body burn extra calories.
The primary health concern that nutrition advocates have with corn is that it may act as a filler, which may cause people to eat too many carbohydrates and too few of more nutrient-dense foods.
According the Tufts University Health & Nutrition Letter, more than a third of corn people eat in the U.S. is in the shape of high fructose corn syrup, or HFCS. This sugar, which is a derivative of cornstarch, has triggered numerous debates about manufacturers adding sweeteners to consumables.
The U.S. Food and Drug Administration (FDA) state that there is no compelling evidence that HFCS is more harmful than other sugars. However, the FDA also recommends that everyone limit their consumption of all added sugars, including HFCS and regular sugar.
Several concerns about corn have become popular, especially on message boards and alternative health sites. We discuss some common concerns below:
Some natural health advocates argue that GMO corn is dangerous. While farmers in America have been using GMO crops for a long time, a 2013 review stated that data is scarce regarding GMO crops and their potential health effects.
A 2012 study, appearing in Food and Chemical Toxicology, found that rats who ate GMO corn experienced negative health effects. However, the journal subsequently retracted the paper amid concerns about fraud and faulty data.
The journal editors never uncovered evidence of fraud, but they did find that the data was inadequate, which fundamentally undermined the study's findings. Also, an anti-GMO organization helped fund the study.
According to 2015 article from Harvard University's Science in the News, both the World Health Organization (WHO) and the American Medical Association have concluded that GMO crops are safe for human consumption.
Corn is high in sugar
Some people confuse corn with HFCS, which is a sugar. Corn does contain naturally occurring sugars, but the amounts are comparable with those present in other starchy vegetables, although slightly higher.
The body cannot digest corn
Corn is high in cellulose, which is an insoluble fiber that the body cannot digest. However, the body breaks down the other components of corn.
Chewing corn for longer can also help the digestive system break down cellulose walls to access more of the nutrients.
Some producers still use an ancient method of corn preparation known as nixtamalization. This process involves soaking and cooking the corn in lime, which is an alkaline solution containing calcium hydroxide.
The producers then wash and hull the corn for processing into food products, such as cornmeal, tortillas, tamales, and others.
Nixtamalization enhances digestibility, flavor, and aroma while reducing mycotoxins, which come from fungal contamination.
Corn is high in fat
Naturally, corn is not high in fat. However, many people prepare it in a way that increases the fat content. Adding butter and other fats or oils to corn can turn it into a high-fat, high-calorie food.
Tips for eating and preparing corn
Corn is edible in its raw state.
Most people prefer to eat corn after cooking it, often with butter, oils, and seasonings.
It is also safe to eat corn raw. Many people find that young, tender corn tastes best when raw.
The kernels can add texture to salads, soups, and casseroles. The USDA offer the following tips for preparing and storing corn:
- Store uncooked corn in the refrigerator for up to 5 days.
- It is safe to freeze cooked corn at zero degrees Fahrenheit for up to 6 months.
- When using prepackaged corn, check for the "best by" or "best if used by" date.
- Remove corn kernels by placing corn stem-first into a bowl of shallow water. While holding the corn, cut kernels away from the cob with a knife.
Corn is not a harmful food, but while it does have several nutritional benefits, it is not particularly rich in any specific nutrient and contains less fiber than other complex carbohydrates.
Some people may have dietary restrictions that can make corn a poor choice to eat. For instance, people trying to reduce carbohydrate intake should avoid corn as it is high in carbs.
People seeking a high-protein diet may want to choose nuts, lean meat, fish, and dairy products instead since they are higher in protein than corn.
There is no harm in eliminating corn from the diet, so it is perfectly safe for people to avoid. However, many products contain corn and corn byproducts, so it is necessary to check ingredient labels. People concerned about the healthfulness of corn should talk to a doctor or dietitian.