this article and also this information on Wikipedia:
Cooked sweet corn has significant antioxidant activity, which has been suggested to reduce the chance of heart disease and cancer, although this has not been definitively proven in practice. "There is a notion that processed fruits and vegetables have a lower nutritional value than fresh produce. Those original notions seem to be false, as cooked sweet corn retains its antioxidant activity, despite the loss of vitamin C," says Rui Hai Liu assistant professor of food science at Cornell University. The scientists measured the antioxidants' ability to quench free radicals, which cause damage to the body from oxidation. Cooked sweet corn also releases increased levels of ferulic acid, which provides health benefits, such as battling cancer. "When you cook it, you release it, and what you are losing in vitamin C, you are gaining in ferulic acid and total antioxidant activity."
I also found this:
Okay....okay.... sweet corn is never going to win awards as some sort of Wonder Food, but it still makes for a healthier dessert option!