I raise chickens at my small farm west of Carrboro, NC. At the moment, there are six members of my all-female flock. In addition to their coop, they have 24/7 access to a 2,500 square foot chicken run. Because I allocate over 400 square feet per chicken, plants grow in the chicken run faster than my flock can kill them by scratching up the ground. I also supplement the volunteer plant life by growing flowers, lettuce, and pumpkins and the like. As a result of my efforts, my chicken run approaches what I perceive to be a sort of poultry paradise filled with worms, bugs, grasshoppers, beetles, and tasty plants. In return for my stewardship, my ladies provide me with the tastiest, most orange-yoked eggs I’ve ever seen. In addition, they might just save my life.
Before I expound further on the lifesaving potential of my chickens, let’s discuss the science behind why humans might want to eat the meat and/or eggs of animals. The first reason that likely crossed your mind was as a protein source. Proteins consist of long-chains of amino acids and comprise some of the most important molecules in your body including DNA, muscle tissues, and enzymes. In order for your body to make all of the proteins it requires, it must have a consistent supply of 20 different types of amino acids. Your body can produce 11 of the 20 on its own. The other 9 need to be included in proteins that you eat. For example, your body cannot produce an amino acid called lysine. To acquire lysine, you must consume proteins that contain it. Then your digestive system disassembles the proteins into their constituent amino acids including lysine. It is quite possible to acquire these 9 amino acids from a vegetarian diet. However, since meat and eggs have high concentrations of protein, eating them provides a more efficient path to acquiring the amino acids that you need compared to vegetables.
Although the food and dieting culture in the United States has given fats a bad reputation, they constitute a vital part of your diet and are utilized by the body for important functions such as cell walls and energy storage. In an analogous manner to proteins, your body can produce many of the fat molecules it needs but there are some that it cannot. As I will discuss again below, one of class of fats that our bodies cannot produce are called omega-3 fats. Here again, you can get all of the fats that you need in your diet from plants, but meat and eggs contain them in higher concentrations saving the omnivore some time.
An under appreciated advantage of eating animals is outsourcing some of the work of eating a variety of plants to them. One of the key drivers of the healthfulness of eating plants is the consumption of phytochemicals, which is a fancy name for chemicals that plants make. Plants make thousands of different phytochemicals, many of which are almost certainly important to our health despite our not yet having a full understanding of how or why. Classes of phytochemicals that you may have heard of include carotenoids – of which beta-carotene is the most well known, and flavonoids. Despite my being acutely aware of the benefits of eating a diverse array of plants, most days my busy schedule limits my success in achieving this goal. Fortunately, I can bridge some of this gap by eating the meat or eggs of an animal that ate plants and accumulated some of the phytochemicals contained within.
Throughout human history, our primary sources of meat and eggs have been cows, pigs, chickens, and fish. None of these animals evolved to eat corn. But in today’s industrial agriculture facilities, including fish farms, corn is the primary feature of their diets. Please note that this is also generally true for chicken meat or eggs labelled “free range” in the grocery store. What “free range” means in this context is that there is a small door at the end of the industrial chicken building leading to a small outdoor pen. However, since all of the corn-based food is inside the building, none of the chickens go outside let alone garner some of their nutrition by foraging.
Feeding animals raised in industrial production facilities with corn rather than with the broad range of foods that they evolved to eat has a dramatic impact on the final food product. To illustrate this point, below is a table that compares the nutritional content of typical eggs from the supermarket versus farm eggs from chickens that derive most of their food from foraging like mine.
As you can see, store and farm eggs are very similar in terms of the content of carbs proteins, and fats. The story on other nutrients is quite different. For example, chickens that eat what chickens are supposed to eat, produce eggs with significantly higher vitamin content. Chickens also divert some of the phytochemicals that they eat into their eggs. So even on days when I don’t manage to eat a sufficient amount or variety of plants, eating my chickens’ eggs provides me with some of the benefits of the plants that they ate.
Let me draw your attention to the difference in omega-3 fats shown on the table. My chicken eggs contain about 3 times more of these fats, fats that my body can’t make, compared to eggs from the grocery storye. For many years now, doctors have noted a correlation between increased consumption of omega-3 fats and reduced risk of heart disease. Recent studies are beginning to indicate that the mechanism by which omega-3s help to prevent heart disease stems from reducing the body’s inflammatory response to tears or other injuries to the linings of arteries and veins. This is a fascinating conclusion. It would be too long to include here, but a key theme of much recent medical research is the centrality of inflammation in many health conditions ranging from heart disease to obesity. Thus, if omega-3s can be helpful in one of these inflammatory-related problems, perhaps it can help in others as well.
Given that both my father and his father struggled with heart disease from an early age, I have always maintained a strong interest in medical research on this topic. Most of this work is fairly high tech and the treatments developed are usually quite expensive. So I enjoy the idea that my decision to raise some chickens for fun could end up being a low tech, low cost approach that just might save my life. I think I’ll go make some scrambled eggs now.
Jeff Danner discussed this week’s column with Aaron Keck on WCHL.
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