Corn Poop's Pollution: A Stinky Environmental Issue

Corn is a staple food for many people around the world, but it turns out that it may not be the most digestible food for humans. The outer shell of a corn kernel is made of a substance called cellulose, which is indigestible for humans. This results in corn kernels often being excreted seemingly undigested. While this is not a cause for concern, it does raise the question of whether corn is worth eating if it is hard to digest. Interestingly, corn production has also been linked to air pollution, with an estimated 4,300 premature deaths per year in the US attributed to it.

Corn kernels are seeds with a waxy, resilient outer coating

Corn kernels are the fruits of corn, also called maize. They are frequently referred to as seeds, but this is incorrect. The kernel is made up of an outer thin covering or shell, consisting of two layers: the pericarp (fruit wall) and the inner testa or true seed coat. The pericarp is the outer covering that protects the kernel and helps to maintain its nutrient value and moisture content.

The outer layer of the kernel has a waxy coating of cellulose. The cellulose molecules are connected by very strong bonds, creating a resilient protective shield. This outer coating is indigestible for humans, and so it is often passed out whole in stools, while the inside of the kernel is digested. This is why you may sometimes see corn kernels in your stool. This is usually not a cause for concern, as the human body is not meant to break down all fibre forms.

The inside of the kernel holds the germ, or corn embryo, which is the only living part of the kernel. The germ is surrounded by a starchy food supply (endosperm) that feeds the seed after it germinates. This makes up about 82% of the kernel's dry weight and is the most widely used part of the kernel. It is used as a source of starch in cooking and is also a key component in fuel, sweeteners, bioplastics, and other products.

The kernel also has a tip cap, and together, the different parts of the kernel make up its total volume, which varies depending on the variety of corn. For example, kernels of popcorn are much smaller than those of grain corn.

The human body can't digest the cellulose in this coating

The human body is unable to digest the cellulose in the coating of corn kernels. This outer layer, or shell, is a waxy, rubbery substance that is difficult to break apart when chewed. It acts as a protective barrier for the germ, or corn embryo, which is surrounded by a starchy food supply (endosperm). The cellulose coating is resilient and indigestible, even for ruminant animals like cattle that are better equipped to digest cellulose.

The human body can digest the material inside the corn kernel, but the hard outer casing is often expelled into the stool. This is because the bonds connecting cellulose molecules are very strong, and the human digestive system cannot break them down easily. As a result, corn kernels can pass through the digestive tract relatively unchanged, with the outer coating remaining intact.

The presence of undigested corn in stool is not usually a cause for concern. In fact, it is quite common for high-fiber foods like corn to be only partially digested. Fiber is beneficial for most people, as it adds bulk to the stool and stimulates the walls of the intestines to move, aiding in the digestion process. However, if undigested corn is accompanied by other symptoms, it may indicate a medical condition, such as irritable bowel syndrome (IBS) or lactose intolerance.

To make corn more digestible and reduce the likelihood of it appearing in the stool, it can be processed through grinding, wet milling, or cooking. These methods break down the hard-to-digest fiber molecules, making it easier for the body to absorb the nutrients in corn. However, it is important to note that easier digestion does not necessarily equate to healthier digestion.

Additionally, the way corn is consumed can impact its digestibility. Eating slower, chewing food more carefully, and steaming vegetables can make it easier for the body to break down corn and maximize nutrient absorption. By reducing the size of food particles, the digestive enzymes can more effectively break down the food, leading to more thorough digestion.

Corn production is a major contributor to air pollution

Corn is the largest agricultural crop in the United States, and its production involves various stages that contribute to air pollution. The top five corn-producing states, including Iowa, Illinois, Nebraska, Minnesota, and Indiana, accounted for 54% of the deaths associated with corn production-related air pollution. The study focused on the specific contributions of different parts of the corn production process, such as fertilizer production, running tractors, and tilling land, which release atmospheric particulate matter (PM2.5). Exposure to PM2.5 has been linked to serious health issues, including cardiovascular problems, respiratory illnesses, diabetes, and even birth defects.

The impact of corn production on air quality and public health is significant, with air quality-related health damages costing an estimated $39 billion annually. The study also suggested that in many parts of the United States, the health damages per bushel of corn exceeded its market price, indicating that the negative impact of corn production may outweigh its economic benefits in certain regions.

Additionally, the total contribution of corn to air pollution is likely even higher than estimated, as the study did not consider the downstream impacts of corn after it leaves the farm, such as transportation and industrial processing. Furthermore, the study's focus on the United States means that the global impact of corn production on air pollution is likely much greater, especially in regions with higher population densities living closer to farms.

While corn is a popular crop and a significant part of the human diet, its production has unintended consequences for the environment and public health. The study highlights the need to address the specific causes of air pollution and find ways to mitigate the negative impacts of corn production on air quality and human health.

Corn is the largest agricultural crop in the US

The versatility of corn is one of the reasons for its popularity. It has hundreds of uses, from animal feed to human food and beverages, industrial uses, and fuel. It is the main energy ingredient in livestock feed, providing the "carbs" for cattle, hogs, and poultry. It is also used to make breakfast cereal, tortilla chips, grits, canned beer, soda, cooking oil, and biodegradable packaging materials. Corn is even a key ingredient in the growing medium for life-saving medicines, including penicillin.

The US exports between 10 and 20% of its total corn production volume, with its largest international markets being Mexico, China, Japan, and Colombia. The US also exports corn to Mexico, South Korea, and Japan, where it is highly prized as a high-quality food ingredient.

The high demand for corn is due to its many uses, but also because it is adaptable and can be grown in a range of different conditions. Seed companies have developed various corn varieties, including hybrid, organic, and bio-engineered types, each suited to different soil and weather conditions. The crop has been improved over the centuries, with farming methods refined and hybrid cropping techniques widely practiced since the late 1880s. This has resulted in corn production in the US being 20% higher per acre than anywhere else in the world.

Corn production accounts for 4,300 premature deaths each year

Corn production is a major contributor to environmental damage, which leads to approximately 4,300 premature deaths each year in the United States alone. The environmental impact of corn farming has been estimated to cost nearly $40 billion annually. The study, published in Nature Sustainability, highlights the human toll of current corn production methods and the urgent need for more sustainable practices.

The primary culprit behind the environmental damage caused by corn production is the excessive use of fertilizers. Ammonia emissions from these fertilizers not only harm the environment but also pose significant risks to human health. The inhalation of ammonia can lead to respiratory issues and other adverse health effects, contributing to the high number of premature deaths associated with corn production.

Moreover, the study reveals that the impact of corn production on human health and the environment varies across different regions. For instance, the deaths caused per bushel in western corn belt states like Minnesota, Iowa, and Nebraska are generally lower compared to eastern corn belt states such as Illinois, Indiana, and Ohio. This variation is likely due to differences in farming practices, population density, and environmental regulations across these regions.

To address the issue, researchers recommend that farmers adopt innovative corn production techniques that minimize environmental harm and protect human health. This includes improving nitrogen use efficiency and relocating corn fields to more suitable areas. By implementing these strategies, farmers can not only reduce the negative impact of corn production on the environment but also decrease the number of deaths associated with ammonia emissions and other pollutants released during traditional corn farming practices.

While it is important to recognize the impact of corn production on the environment and human health, it is essential to note that seeing corn in one's stool is usually not a cause for concern. Corn kernels have an outer shell made of cellulose, an indigestible material. The body digests the inner material, while the hard outer casing is expelled through stool. This is a normal process and does not indicate any health issues.

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