Corn has a way of staying intact from plate to poop. The bright yellow kernels found in our favorite summer dishes can show up – seemingly undigested – in the toilet hours later. How does corn survive the digestive system? And, more importantly, should you eat a food that is difficult to digest?
Turns out your digestive system does more work than you think, so don’t skip the corn just yet. The yellow kernels in your poop are actually the outer layer of the corn kernel.
Corn kernels are seeds that contain valuable genetic material. The key to the seed’s survival is the waxy, yellow outer coating that protects the genetic material from weather, pests and transport. The fact that it is difficult to break is actually ideal for the plant. The outer layer owes its strength to a tough fiber called cellulose, which humans do not have the right enzymes or gut bacteria to digest.
Even ruminant animals, such as cattle, which are much better equipped to digest cellulose, cannot always fully digest corn. Although cattle don’t eat the same sweet, soft corn that we do (they eat harder, more mature corn that can be stored long-term), whole kernels also show up in their droppings. Researchers have done the dirty work of collecting those expelled kernels and analyzing their nutritional content.
The good news is that cellulose makes up only 10% of corn. Therefore, the other 90% is useful nutrition. Corn is also a good source of dietary fiber, starch and antioxidants known as carotenoids, which give vegetables like corn and carrots their stunning colors. However, there are fewer carotenoids in corn than in a typical serving of leafy green vegetables, according to a 2019 Tufts University report.
There’s one way to make corn more digestible and completely disappear from your poop: process it. “The more you process it, the easier it is to digest.” This is true for both humans and animals. Grinding, wet milling, cooking…each processing step breaks down those hard-to-digest fiber molecules a little more, he explains.
In fact, most of the corn consumed is processed. The Tufts University report estimates that each American consumes 70 kilograms of corn per year. The vast majority of that corn is not the hard-to-digest kernels nibbled off the cob, but corn turned into mushy tortillas, potato chips, popcorn and, most importantly, high-fructose corn syrup.
However, easier to digest should not be confused with healthier. A look at the nutrition information shows that common processed corn products, such as corn oil and high fructose corn syrup, lose most of their fiber and beneficial nutrients during processing
Corn kernels in your poop may be strange, but it’s not bad for your health. In fact, it’s a sign that you’re eating corn in one of its healthiest forms. The best tip to avoid seeing whole kernels in the toilet: chew carefully.
So is corn digested?
As we have already mentioned, it is the outer part of the kernel, made of cellulose, which is not digested and usually appears in the stool, which means that corn is digested except for its outer layer
