About Sweet Corn
Different varieties of corn highlight different combinations of antioxidant phytonutrients. In the case of yellow corn, carotenoids lead the way and provide especially high concentrations of lutein and zeaxanthin. Blue corn is unique in its anthocyanin antioxidants. One particular hydroxybenzoic acid in purple corn—protocatechuic acid—has recently been linked to the strong antioxidant activity in this corn variety.
Most studies of disease and risk reduction from dietary antioxidant intake have not looked specifically at corn and its impressive combination of antioxidants. However, in several small-scale studies, corn has been directly mentioned as a food that was important in overall antioxidant protection and a contributing factor in the decreased risk of cardiovascular problems. Some of the mechanisms for decreased cardio risk may be related to other properties of corn's phytonutrients that go beyond their antioxidant properties. For example, some of the phytonutrients in corn may be able to inhibit angiotensin-I converting enzyme (ACE) and help lower risk of high blood pressure in this way. We suspect that future studies will further confirm the important role of corn's phytonutrients in reduction of risk for a variety of health problems, and that antioxidant and other properties will play a key role in this risk reduction.
One great piece of news about corn's antioxidants involves the practice of drying corn (still on the cob) or separated corn kernels. Research studies have shown that the drying of corn in temperature ranges as high as 150°-200°F (65°-93°C) does not significantly lower corn's antioxidant capacity. This research confirms the wisdom of many North American and Mesoamerican cultures which relied on naturally-dried corn in the preparation of meal foods, especially during the winter months.
Interestingly, recent research has determined that the percent of amylose starch found in corn may be related to its antioxidant capacity. Higher amylose corn varieties have shown higher antioxidant capacity in some preliminary studies. While the jury is out on the exact meaning of these findings, this research reminds us to keep an open mind about the potential importance of antioxidant health benefits from corn.
Anyone who has eaten fresh corn-on-the-cob or freshly popped popcorn knows how satisfying this food can be to chew. Some of that satisfaction comes from corn's fiber content. At 4.6 grams of fiber per cup, corn is a good fiber source, and in research studies, corn intake is often associated with good overall fiber intake. For example, persons who eat popcorn tend to have 2-3 times more overall whole grain intake than persons who do not eat popcorn, and they also tend to have higher overall fiber intake as well.
Corn fiber is one of the keys to its well-documented digestive benefits. Recent research has shown that corn can support the growth of friendly bacteria in our large intestine and can also be transformed by these bacteria into short chain fatty acids, or SCFAs. These SCFAs can supply energy to our intestinal cells and thereby help lower our risk of intestinal problems, including our risk of colon cancer. The amount of corn fiber analyzed in recent studies has been relatively high at 12 grams per day. That's the same amount provided by about 2.5 cups of fresh corn. While that amount might be more than any person would consume in a single meal, it's an amount that a person might easily eat over the course of several days. We suspect that future research will demonstrate the risk-reducing effects of smaller amounts of corn consumed over a longer period of time.