GMOs: The scarlet letters of the grocery aisle?

By Shanley Chien

You walk down the aisles at Whole Foods spotting milk, cookies, pasta, and a variety of other products with the “Non-GMO Project Verified” label. The label tells you the foods don’t contain genetically modified organisms  – GMOs.

But the image of a butterfly sitting on a blade of grass shaped like a check mark subconsciously reassures you that this product is “safe.” After all, if it’s safe enough for a butterfly, it’s safe enough for you and your family. You put it in your basket, perhaps because people like Dr. Oz and food blogger Vani Hari of Food Babe tell you GMOs are unhealthy.

GMOs add to the nutritional value and preservation of foods and most scientists vouch for their safety. But critics abound.

“We have the whole government working against us,” Hari said in an interview on the Carolina Connection Talk Radio. “They don’t want Americans to figure out that these could be causing health issues, that they haven’t been tested, and they are increasing pesticide and herbicide use.”

Organizations and advocacy groups such as the Non-GMO Project, Dr. Oz, Food Babe, and other anti-GMO crusaders say GMOs are unnatural and unhealthy, according to their websites.

Recently, Hershey’s Chocolate announced it will remove all genetically engineered (GE) ingredients from its popular lineup of candy bars by the end of the year. Social media, emails, and phone calls from consumers and the anti-GMO advocacy group GMO Inside pressured the company into making the move away from GE ingredients, GMO Inside stated in a press release.

The group also reported that Hershey’s will replace GM sugar beet with cane sugar and use a non-GM version of soy lecithin. Hershey’s new initiative to “make [its] products using ingredients that are simple and easy-to-understand” also means there won’t be any more artificial flavors or high fructose corn syrup, and will be gluten free, the group said.

“I think if you don’t know much about [the science], it’s very easy to be misled by groups who appear to have an interest in protecting you,” said Dr. Alison Van Eenennaam, professor of animal biotechnology and genomics at the University of California-Davis.

According to the Non-GMO Project’s website, the company earns more than $11 billion in annual sales and have more than 27,000 products verified with their seal. But purchasing a product with the “Non-GMO Project Verified” stamp doesn’t necessarily mean your food is GMO free: The company states its verification seal “is not a ‘GMO free’ claim.”

“Given the high number of specific, key commodity GMO crops (soy, corn, sugar beet, canola, cotton, alfalfa, etc.), it’s not scientifically or legally defensible to call something GMO free,” said Caroline Kinsman, communications manager at the Non-GMO Project.

Kinsman explained that the Non-GMO Project provides a “rigorous voluntary verification program for GMO avoidance,” using a polymerase chain reaction (PCR) test to determine whether or not a raw ingredient contains GMO content. PCR testing replicates a piece of DNA and makes thousands to millions of copies of that specific segment so machines can detect any traces, but this method can only be used if tested at the raw-ingredient level.

“Say I’m making a chocolate chip cookie. A test is basically going to look for DNA in the final cookie product,” Van Eenennaam said. “In this cookie there would be sugar, and sugar can be derived from GE sugar beets or it might be derived from non-GE sugar cane, but there’s no way they’d be able to [scientifically] test that [in the final stage].”

Amid the heated public debate and confusion, it’s important to understand what exactly GMOs are.

Contrary to popular misconception, people have been genetically modifying crops for thousands of years. (GMO Answers)
Contrary to popular misconception, people have been genetically modifying crops for thousands of years. (GMO Answers)

GMOs – Dissecting the Genetics

Dennis Halterman, research geneticist at the U.S. Department of Agriculture’s Agricultural Research Service and University of Wisconsin-Madison, has dedicated his career to how plants interact with pathogens on a molecular level and used GMO technology to develop a natural plant resistance to diseases without the use of chemicals.

He explained that humans have been genetically modifying food since the beginning of agriculture and there are now various methods to safely genetically engineer thanks to new science.

Common Types of Genetic Engineering

Common types of genetic engineering. (Shanley Chien/Medill)


The most traditional way is crossbreeding, which entails taking the flowers and pollen from a plant that has a desired trait (like resistance to viruses, fungi, bacteria, etc.) and crossing them with another plant that is susceptible but has other good traits (like high yield). This process for creating hybrids has been used since the dawn of agriculture and is done by planting various seeds in the field and seeing which ones grow with the desires traits.


With advanced biotechnology, scientists can now take specific genes and move them individually into a new variety by using agrobacterium, a type of natural soil bacteria that introduces a segment of its own DNA into the genome of a plant, carrying with it a specific set of instructions for the plant to carry out. Halterman explained that, although using agrobacterium still produces random results, scientists are able to counter the random nature of this method by playing the numbers game.

“We will make hundreds or thousands of plants, each with a different insertion of the gene and find the one out of all those that behaves as we expect it to,” he said.

Gene Silencing

The USDA-approved non-browning Arctic apples that made the news last month were achieved by another method of genetic modification called gene silencing. Over the past 10 to 15 years, scientists have used this method to “turn off” certain genes without introducing DNA that encodes a protein.

Instead, the process occurs at the ribonucleic acid level – RNA for short. RNA is a single stranded molecule responsible for coding and expressing genes. Because many viruses produce double-stranded RNA (dsRNA) throughout their life cycle, plants can recognize the presence of dsRNA and, as a defense mechanism, eliminate it. Scientists discovered that they can use the plant’s inherent defense system to control gene expression, by producing a dsRNA of a targeted gene that the plant will perceive as a virus and sending a signal to the plant’s control center to chop up the sequence so that it can no longer function.

Additionally, new gene editing technology is so advanced now that scientists can target exactly where they want to introduce a piece of DNA into the plant’s genome. This precision allows them to more accurately insert, replace, or remove DNA in parts of a genome.


In the case of the Arctic apples, turning off the gene that controls browning would help limit food waste for consumers and the planet.  Approximately 40 percent of food produced in the U.S. goes to waste as it passes through the food supply chain, according to a study conducted by the U.S. Environmental Protection Agency. This scientific advancement has the potential to mitigate that issue.

But the technological advancements scientists have made in recent years in GMOs not only benefit farmers: They also help to alleviate the increasing global population and third world hunger, Halterman said.

According to the United Nation’s World Food Programme, “some 805 million people in the world do not have enough food to lead a healthy, active life. That’s about one in nine people on earth.” Additionally, “poor nutrition causes nearly half (45 percent) of deaths in children under five — 3.1 million children each year.”

Global vitamin A deficiency, based on World Health Organization data. (Photo by Wikipedia)

Scientists were not only able to create a genetically engineered fortified grain to combat vitamin A deficiency (called golden rice), but they can also help hunger-stricken nations that don’t have access to the same pesticides as the U.S. and other first world nations still be able to grow high-yield crops that resist drought, insects, and diseases, Halterman said.


Of course, GMOs are not without its problems, as well. Like many big issues, the topic of GMOs is very nuanced, especially when you throw in corporate farming giants like Monsanto — a leading agricultural biotech company of GE seeds and herbicide brand Roundup — dominating the market share.

“On the food safety side, I personally don’t have any concerns based on the published literature with the safety of the products that are out on the market right now,” said Dr. Peggy Lemaux, professor of crop biotechnology at the University of California-Berkeley. “But I do have some issues with the speed with which things have come out and also the repetitive nature of the changes they’ve made.”

Lemaux referred to the overuse of certain technology, like Monsanto’s Roundup Ready and the biological pesticide Bacillus thuringiensis (or Bt), for herbicide tolerance and insect resistance in crops.

“Because a lot of these have been used over and over again, year after year, in the same crops and in the same field, insects and weeds develop resistance. They mutate,” she said.

Although Monsanto states on their website that “GM crops have been reviewed and tested […] and have been shown to be as safe as conventional crops,” they acknowledge that there are potential challenges based around resistance that need to be addressed. The company stated in a press release that  there are a small number of insects that have a pre-existing resistance to certain Bt proteins. But with current farming practices, “it is possible that too many insects in a field could develop a tolerance to a Bt protein and cause significant damage or destruction.”

Although a valid concern, other scientists — including Halterman and Van Eenennaam — have attributed that insect and weed resistance to the basic concepts of agriculture and evolution.

Weed and insect resistance is “absolutely a concern, but people have been aware of that forever anyway,” Halterman said. “It doesn’t matter what the pesticide or herbicide is. That’s not anything new. We’d be concerned if we weren’t using Roundup and were using something more dangerous like 2,4-d or more toxic chemicals. We’d still be stuck with weed resistance.”

“Weeds developed a resistance to those chemicals because weeds evolve over time — as do insects, as does everything,” Van Eenennaam said. “They evolve around different control mechanisms, even mechanical mechanisms.”

She used the example of using a mower to take care of weeds and how they’ve developed so that, instead of sprouting up to a stalk, they spread across the ground so they avoid getting cut by the blade and the mower.

“Weeds are always developing resistance to things, so this idea that GMOs are uniquely associated with the development of resistance is [odd],” she said, adding that herbicide resistance can be alleviated by rotating chemical herbicide usage with other weed control techniques.

Physiology and GMOs

“We think there is no argument on health and safety,” said Karen Batra, director of communications at Biotechnology Industry Organization, who speaks on behalf of the biotech industry (including Monsanto). “The scientific consensus is that health and safety are simply not an issue. Any food product containing genetically modified ingredients are exactly as healthy and safe as their conventional counterparts.”

Monsanto also stated in a press release that they conduct extensive tests to determine the safety of their products. Kevin Glenn, product safety center lead at Monsanto, said they supplement their evaluation by studying the toxicology and physiology of the rats to determine if there could be any adverse effects on humans.

“All of these assessments have some known association with important health or physiological function in the animal that would be impacted and give us a clue if there is some toxicity,” Glenn said.

Glenn and other third-party scientists said there are currently no commercialized biotech products that have been associated with “an actual hazard to humans or animals.” Yet, even with all the evidence showing GMOs don’t pose health risks, the scientific community still struggles to convince the public of GMO’s safety.

The divisive tension between the anti-GMO and pro-GMO camps leaves many people uncertain about their food choices, especially about the health effects of consuming GM food, and wondering if they pass along a piece of DNA they ingested to their children. But Lemaux said there’s a flaw in that way of thinking.

“We’ve been eating genes since the beginning of time. Everything we eat, particular fresh stuff, has [foreign] genes and DNA,” Lemaux said. “This process happens all the time: We’re eating [genes and DNA, and they all get broken down. So the genes are not going to go through your small intestine wall and somehow go through your veins and get into your blood. It’s just not going to happen.”

Van Eenennaam conducted an in-depth literature review of 29 year’s worth of animal productivity and health information. After studying field data of over 100 billion animals given non-GE and GE animal feed, she discovered that there are no health risks. She said scientists have published long-term studies of animals on GE-based diets and concluded “that GM plants are nutritionally equivalent to their non-GM counterparts and can be safely used in food and feed.”

Oklahoma State University’s Department of Agricultural Economics published a survey in January 2015 that showed 82 percent of people wanted food with GMOs to be labeled, an initiative that the California state senate voted down last year.

But the survey also showed that just as many people (80 percent) also supported mandatory labeling for foods containing deoxyribonucleic acid, more commonly known as DNA. Considering that all food has DNA, these results are indicative of the general population’s lack of scientific knowledge.

“If you’re starting at that level of information with people, then having them understand scientific studies that were done […] is very difficult,” Lemaux said.

But if beloved science educator Bill Nye the Science Guy can change his mind about GMOs, maybe GMOs are turning the tide.

“There’s a chapter in [my book] which I’m going to revise,” said Nye backstage after his appearance on HBO’s Real Time with Bill Maher on Feb. 20. “It’s about genetically modified food,” he said. “And I’m very excited about telling the world. When you’re in love you want to tell the world.”

Photo at top: Genetically engineered rice plant. (BASF)