The purpose of this post is to provide you with a clear and easy-to-understand explanation of GMOs - genetically modified organisms. Why learn about GMOs? Apart from learning fundamental concepts about food and biology, GMOs are a very misunderstood topic. In fact, of all topics in science, opinions regarding GMOs have the greatest disparity between what scientists believe, and what the lay public believes. In a 2016 Pew poll, 88% of scientists believed GMOs were safe to eat, while only 38% of the general public thought so. The more one opposed GMOs, the less they understood them. Many of my colleagues can’t give me a basic definition of a GMO. Can you?
Food is an emotionally loaded topic
What complicates learning about GMOs is that food for some people is a very emotionally loaded topic. In our hierarchy of needs as animals, "What is safe to eat?", is as primal, and as critical a question as it gets. Two of our six primary emotions, disgust and fear, are hard-wired to protect us from unsafe things, like putrid meat and feces. It's easy to see how these emotions can be triggered by GMOs: big companies messing with our food for profit, and sacrificing safety for higher yield and shelf-life. It wouldn’t be the first time companies made products bad for our health.
However, it's also important to understand that other for-profit industries, like the "wellness" and organic food industries, thrive from these emotions. They will go as far as showing you graphic images of tumors in rats from that single study on GMOs no one could replicate. They're motivated to spread the message that modern food is "unnatural"and riddled with "toxins". They know consumers will pay premium prices for"natural” food. They know consumers will even pay premium prices for a natural sounding label that makes no sense, like "gluten-free" orange juice, or "non-GMO" salt.
Please keep this in mind when you learn about GMOs…
The history of the tomato
To teach you about GMOs let me begin by asking some questions about the tomato…
Q: What part of the world do tomatoes come from?
A: Although it's tempting to think Italy, this is the wrong answer. Tomatoes are actually native to the region around Peru. They were only brought to Europe after Columbus. The ancient or "wild" tomato is pictured below. You can observe it’s small and purple with a thick skin. It yielded very little calories, and tasted horrible.
However, well before it was introduced to Europe, ancient Peruvians were able to breed it into the tomato pictured below.
Which leads to the next question...
Q: How did they do this?
A: About 10,000 years ago they began to plant fields with hundreds of wild tomatoes. Occasionally, one of them would be bigger, or juicier, or more pest resistant than the rest. They would take the seeds from that tomato, and plant them the next season. And so on, and so on, until they bread the big tasty calorie-yielding tomato we know today. This process is called plant breeding. Which leads to the next question...
Q: How does plant breeding work? How does the occasional tomato in the field become different from the other tomatoes around it?
A: Genetic mutation. Genetic mutations happen ALL the time in nature. The genetic code is copied every time a cell divides, and on average, a single error is made. Not bad, but considering the billions of replications in the billions of organisms, that's a lot of genetic mutation and variation.
Natural selection vs artificial selection
These random mutations are actually essential to life on earth. They are the driving force behind evolution and how organisms adapt. Some mutations are bad for survival, some are good for survival, and some do nothing. The mutations good for survival are passed on. They are “selected" by nature. In deed, all life on earth is just one long chain of mutations.
Mutations are also the cornerstone of breeding. However, instead of nature selecting the mutations, the farmer or breeder selects the mutations. This is why breeding is also called, "artificial selection".
Testing genetically modified tomatoes for safety
The breeding of tomatoes by ancient Peruvians farmers lead to tremendous genetic modification, sometimes thousands of genes. This begs the next question...
Q: Did they test their genetically modified tomatoes for safety? Did they ensure those tomatoes didn't cause cancer at age 60?
A: No. Obviously not. Our ancient ancestors were very limited in what they could test for. They could determine if a food was poisonous if it made them ill or caused death directly after consumption, but they couldn't determine if it caused cancer at age 60. Linking long term consumption of foods to disease is extremely difficult without the techniques of modern epidemiology; and even WITH modern epidemiology we still can't agree on even basic foods (egg are good, eggs are bad).
Furthermore, the goal of our ancestors was to make it past their first birthday or past the "hunger season". If a genetically modified food would kill them at 60, but yield more crop, more calories, and feed more people throughout the year, relatively speaking, it was a winner.
Q: But, what about the "wild" tomato? Did they test them for safety?
A: No. As above, our ancient ancestors could only determine if something was poisonous, not long-term effects. There was no reason to assume that the "wild" variety was safe simply because it came from "nature". To make this assumption is a logical fallacy called, "the appeal to nature" - what is natural is good for you. In reality, the opposite is often true. Natural selection shapes plants and animals for their OWN survival, not for ours. Let me demonstrate this point with another question…
Q: Why do certain plants produce neurotoxins (like opium, cocaine, nicotine, and THC) that serve no direct function for the plant?
A: They are all insecticides. Plants are unable to run away from their greatest predator, animals. So they wage chemical warfare and synthesize neurotoxic drugs for the sole purpose to prevent being eaten. Plants are not our friends. We just try to pick the ones that don't kill us.
The take home message is that foods are complex. They are packages consisting of thousands of chemicals. Organic chemicals, but chemicals nonetheless. Long term safety of food, whether "natural" or not, genetically modified or not, is difficult to determine. Unfortunately, trusting "nature" or our ancestors are not reliable strategies.
All your food is genetically modified
Beginning 10,000 years ago, farmers across the world began applying breeding techniques to every wild plant and animal they could get their hands on. This is the "agricultural revolution". Today, every food in your market (including tomatoes) is a product of breeding. They're all genetic modifications of the wild organism.
Q: Does this include the products at my organic market?
A: Yes. Unless labelled "wild" ("wild" rice, "wild" mushrooms, "wild" blueberries, "wild" caught salmon, etc.), everything at an organic market is genetically modified. For example, cabbage, broccoli, kale, and cauliflower are all genetic mutations of a single wild plant, the wild mustard plant (see below). Even "Ancient grains" like Quinoa, are domesticated versions of their wild type.
The definition of a GMO?
At this point, it's reasonable if you’re confused about the definition of a GMO. If almost every product at your organic market is genetically modified, included the ones labeled "NON-GMO", what is a GMO?
I will be answering this in Part 2 of this post…coming soon.
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