The artificial origin of our food – 12/21/2023 – Fundamental Science

“Everything that is natural is good”: the assumption impacts what we understand by food, therapies, medicine, consumption patterns and lifestyle. Faced with two options, one associated with what we consider to be natural and the other perceived as artificial, we tend to choose the first. The medicine comes from the plant, instead of the tablet synthesized in the laboratory; the cotton fiber of the t-shirt instead of the synthetic one; valuing the “naturalness” of certain behaviors, as if this made them more acceptable – someone pointing out that chimpanzees can be violent, justifying human violence.

But the naturalistic fallacy is undoubtedly more present in what we eat: healthy and natural food have become almost synonymous, and eating “natural products” seems to be the best way to take care of your health. However, almost everything we eat has been drastically altered by humans. Especially the plants.

We have been modifying our food for a long time and in many ways. The agricultural revolution began around 11 thousand years ago, when, in different places on the planet, we realized that we could plant part of the seeds we collected, thus ensuring a more predictable supply. We quickly selected larger seeds, plants that produced more and with the characteristics we liked most, such as ease of cooking, as well as flavors and aromas.

The original species, which lived in their native environment without our interference, slowly became very different from, and codependent on, humans. Previously difficult to digest, not very tasty and insufficient to feed a large population, today edible fruits, leaves and roots are robust, attractive and full of sugar, fat and protein. The list is long: potatoes, carrots, tomatoes, eggplant, barley, corn, rice, beans, lentils, coffee, cocoa. Just as the greyhound, Pomeranian and Saint Bernard are modified wolves, the plants we consume most were also created by artificial selection.

Our foods are, therefore, our creations. Cabbage, broccoli, kale, cauliflower, Brussels sprouts are a single species; they all derive from the same wild ancestor – spontaneous mutants that pleased us and that we kept on our plantations. Fruit trees such as apples, oranges and grapes are generally produced by clonal propagation, a process that occurs when a mother plant with interesting characteristics – which also arise through spontaneous mutations – is used to generate genetically identical seedlings. And these clones are often grafted: two distinct plants are joined at the stem, one providing its roots and the other the crown and, in the future, the fruits. A vegetable Frankenstein, which humanity has been using for centuries.

There is also the much more recent kiwi. From a fruit of Chinese origin the size of a grape, the gooseberryan artificial selection was carried out in New Zealand for size, flavor and durability, and the result was named kiwifruitin honor of the country’s typical bird and New Zealanders’ nickname, in the middle of the 20th century. In less than a hundred years, a new fruit was created by artificial selection.

The green revolution of the 1950s and 1960s brought other changes to our table. The addition of fertilizers, important for increasing grain production, also contributed to the development of the plant, which grew a lot and fell over, causing losses and making it difficult to manage the machines. One solution: bombard wheat seeds, one of the main grains, with radiation, inducing random mutations in the genome.

Many of these mutations were disastrous; others were imperceptible, while still others made plants smaller, less prone to tipping over and more productive. These are the semi-dwarf varieties. Crossbreeding introduced similar mutations into rice and corn, now available all over the world – you probably eat them. Interestingly, the genes altered by these mutations were only identified in the 2000s.

And they are not the only ones: the grapefruit or pomelo, for example, results from a hybrid – the crossing of two different plants, with the preservation of the original chromosomes – which subsequently underwent mutations through radiation to produce varieties with very red pulp. Similar methods to generate new varieties with characteristics of commercial interest have been used for decades in oranges, tomatoes, grapes, sunflowers, barley and even ornamental plants.

The distinction between natural and artificial often does not work. Today it is possible to insert genes from other varieties, plant species or even very distant organisms into the plant genome, adding or modifying characteristics in a more precise way. The most used method is based on the natural ability of a bacterium capable of introducing part of its DNA into the plant genome. Yes, this happens all the time in nature.

Not long ago, we discovered that all consumed sweet potato varieties – also artificially selected by humans – contain bacterial DNA in their genome. Sweet potatoes are a natural transgenic, and that doesn’t make it any less safe. Another example: the transgenic BT corn variety produces a protein that prevents the plant from being consumed by a caterpillar, protecting the plantation. This same protein, normally present in bacteria Bacillus thuringiensis, is considered a natural pesticide and has been used to control caterpillars in common crops. Our perception of transgenic corn warns us that “artificial is dangerous”, while the same molecule, produced in a way considered natural, seems to us to be risk-free.

Food is safe or healthy regardless of whether it has a natural or artificial origin. Products for human consumption must be tested carefully, and the results will only be valid for the product under test, on a case-by-case basis, regardless of origin. In the era when even more precise modifications of plant genomes are possible through gene editing, it is crucial to understand that we are always altering what we consume. It is important to pay attention to what changes we will make, whether they benefit the populations that need them most and whether they are environmentally sustainable.

The future of humanity will require diverse, universal and abundant food, and it will be essential to overcome this cognitive bias so that we can use all available tools to solve the multiple problems we face, which tend to be multifactorial and local. Natural or artificial, the important thing is to find solutions.

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Felipe Klein Ricachenevsky is a professor and researcher at the Federal University of Rio Grande do Sul.

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