Are Soybeans GMO? What to Know About Soy in the US

Soybeans grown in the United States are GMO in the vast majority of cases. The Food and Drug Administration reported that 94 percent of soybeans planted in the US in 2020 were genetically engineered, and the Non-GMO Project puts the current figure at roughly 95 percent. Most of these soybeans carry a trait that lets them survive spraying with the herbicide glyphosate, sold under the brand name Roundup. That trait, first sold by Monsanto in 1996, spread quickly because it let farmers control weeds without damaging their crop. Unless a package specifically says organic or non-GMO, the soy inside it almost certainly comes from a genetically modified plant.

Are Soybeans GMO in the US?

Yes. Multiple sources tracking US agriculture put the share of genetically modified soybeans somewhere between 90 and 95 percent of the entire crop, and that share has barely moved in over a decade.

Non-GMO Project estimates put the current figure at roughly 95 percent, Soy Connection and the International Food Information Council both cite figures above 90 percent, and EcoFarming Daily notes that Roundup Ready soybeans alone, the original glyphosate-tolerant variety, are planted on 90 percent of US soybean acres.

That share has stayed close to this ceiling since the early 2000s, when Roundup Ready adoption first climbed past 90 percent of planted acres. Conventional, non-GMO soybeans still exist in the US, but they make up a small minority of total production, and shoppers who want to avoid them specifically need to look for an organic or non-GMO verified label rather than assume a plain bag of soybeans or bottle of soybean oil is free of genetic engineering.

What Makes GMO Soybeans Different from Conventional Soybeans?

One difference between GMO and conventional soybeans is how they are developed. Conventional breeding often mixes all genes from two sources, while modern biotechnology can transfer a particular beneficial gene into a plant. Many GMO soybean varieties are designed to tolerate particular weed killers, giving farmers different weed-control options. The first herbicide-tolerant GMO soy inserted DNA from a glyphosate-resistant bacterium into soy, according to the Non-GMO Project.

Herbicide tolerance is common, but it is not the only trait found in GMO soybeans. GMO soy can also be modified for pest resistance and altered oil composition. FDA says genetically modified soybeans with healthier oils can replace oils containing trans fats.

Wikipedia describes soybean oil traits that include increased oleic and stearic acids and decreased linolenic acid. FDA says genetic modification can also be used for higher yields, reduced crop loss, longer storage life, improved appearance, improved nutrition, or a combination of traits.

How Did GMO Soybeans Become the US Standard?

GMO soybeans became the US standard within a few years of regulatory approval. Regulators cleared the first genetically engineered soybean, a variety called GTS 40-3-2, for commercial planting in 1994. Monsanto began marketing it under the Roundup Ready name in 1996, and adoption spread fast once farmers saw the weed control savings for themselves. By 2016, Monsanto had introduced Roundup Ready Xtend soybeans, engineered to tolerate both glyphosate and a second herbicide called dicamba, developed after some weeds started surviving glyphosate on its own.

Global Adoption Beyond the US

Other countries followed the US closely once the trait proved profitable for farmers. Canada approved GMO soybeans in 1995, and Japan and Argentina followed in 1996, the same year Monsanto began marketing Roundup Ready domestically. Uruguay adopted the trait in 1997, Mexico and Brazil in 1998, and South Africa in 2001. By 2014, genetically engineered soybeans covered 82 percent of all soybean farmland worldwide, or about 90.7 million hectares, a unit of land measurement equal to roughly 2.5 acres.

Year	Country or Region
1994	United States (commercial approval)
1995	Canada
1996	Japan and Argentina; US marketing begins
1997	Uruguay
1998	Mexico and Brazil
2001	South Africa

What Other Traits Have Been Bred into Soybeans?

Breeders have added several traits to soybeans beyond the original glyphosate tolerance, mostly to solve problems that showed up after Roundup Ready became widespread. Dicamba tolerance came next, engineered specifically as a backup once some weeds began surviving glyphosate.

Later varieties stacked multiple traits together, combining herbicide tolerance with a Bt protein that resists certain insects. DuPont Pioneer took a different approach with its high oleic acid soybeans, launched in 2010, which improve cooking oil quality rather than weed control. HB4 drought-tolerant soybeans, approved starting in 2015, were engineered to handle dry growing conditions instead.

Genetic Trait	Introduced	Purpose
Roundup Ready (GTS 40-3-2)	1996	Glyphosate tolerance
Dicamba tolerance	Early 2000s onward	Backup herbicide as weeds resisted glyphosate
Roundup Ready Xtend	2016	Dicamba and glyphosate tolerance combined
High oleic acid	2010	Improved cooking oil quality
HB4 drought tolerance	2015 and later	Withstands dry growing conditions

Why Did Farmers Need a Second Herbicide Trait?

Farmers needed dicamba tolerance because glyphosate alone stopped working as well over time. The Non-GMO Project explains that dicamba tolerance was developed as a direct response to weeds becoming resistant to glyphosate after two decades of heavy, repeated use on the same fields.

Spraying the same chemical on the same land year after year gave any naturally resistant weeds a chance to survive, reproduce, and spread, a pattern common to herbicides and pesticides generally. Dicamba, and later the combined Roundup Ready Xtend trait, gave farmers a second chemical option to fall back on once glyphosate resistance became a widespread problem in certain regions.

Where Do US Soybean Crops Actually Go?

Most US soybeans never reach a grocery shelf as whole beans. Just over 70 percent of the crop becomes animal feed, about 5 percent is turned into biodiesel, and roughly 25 percent ends up in food for human consumption, mostly as highly processed ingredients like oils, ground meals and starches.

To see what that looks like in practice, picture 100 bushels of soybeans coming off a US farm. About 70 bushels go to livestock feed for cattle and poultry operations. Roughly 5 bushels are processed into biodiesel fuel for vehicles and equipment. The remaining 25 bushels move into the human food supply, and even then, most of that portion is crushed into soybean oil or meal rather than sold as edible soybeans or tofu. Very little of a typical harvest reaches consumers as a recognizable soybean product; almost all of it changes form first.

This breakdown matters for anyone trying to avoid GMO soy through diet alone. Cutting out edamame or tofu removes only a sliver of total soy exposure, since cooking oil, animal feed passed through meat and dairy, and processed ingredients hidden in packaged foods account for the bulk of how soy enters the American food supply.

Are GMO Soybeans Safe to Eat?

Yes, according to the mainstream scientific and regulatory consensus. The FDA states that GMO foods are as healthful and safe to eat as their non-GMO counterparts, and the American Association for the Advancement of Science lists GMO crops among the most extensively tested crops ever added to the food supply. World Health Organization statements say no effects on human health have been shown from eating genetically modified foods.

The International Food Information Council adds that GMO soybeans look the same, taste the same, and carry the same nutritional profile as conventionally grown soybeans. That consensus rests on decades of regulatory review and peer-reviewed research, though public debate about long-term effects continues in some circles, and anyone with specific health concerns, allergies, or an existing medical condition should talk to a doctor before making major changes to their diet.

What One GM Soybean Rat Study Found, and Could Not Show

One 120-day experiment found no adverse effects among Sprague-Dawley rats fed a diet containing 70% GM soybean. Its findings apply to that rat experiment and cannot by themselves establish outcomes in humans.

Study element	GM-soy rat group	Non-GM-soy rat group	Comparison or limit
Diet and animals	Diet containing 70% by weight GM soybean	Diet containing 70% by weight non-GM soybean	Sprague-Dawley rats were followed for 120 days.
Body weight, blood, and chemistry	Monthly and final body weight, hematology, and serum-chemistry variables were assessed.	Monthly and final body weight, hematology, and serum-chemistry variables were assessed.	No statistically significant differences were found between the groups.
Stool bacteria	Six bacterial strains and total stool-bacteria counts were assessed.	Six bacterial strains and total stool-bacteria counts were assessed.	No statistically significant differences were found at 120 days.
Human relevance	Results concern rats eating a 70% soybean diet.	Results concern rats eating a 70% soybean diet.	The experiment cannot by itself establish human outcomes.

Results covered monthly and final body weight, hematology variables, serum-chemistry variables, six stool bacterial strains, and total stool-bacteria counts. None of those tested measures differed statistically significantly between rats in the GM-soy and non-GM-soy groups at the study’s endpoint.

The study concluded that GM-soy consumption did not show adverse effects on the physiological variables or gut microbiota it tested in Sprague-Dawley rats. Researchers also called for further investigation of antibiotic resistance in gut microbiota after GM-food consumption, placing a defined research question alongside the experiment’s narrow findings.

Do GMO Soybeans Mean More or Less Herbicide Use?

Sources disagree, and the disagreement comes down to how herbicide use gets measured rather than a simple yes or no. Industry groups including the FDA, Soy Connection and the International Food Information Council say GMO soybeans let farmers use fewer, more targeted herbicide applications instead of a mix of broad-spectrum chemicals. Soy Connection cites a 43 percent drop in greenhouse gas emissions per bushel and a 47 percent gain in land use efficiency per bushel since 1980, figures that describe output relative to resources used.

Critics measure it differently. The Non-GMO Project reports that glyphosate use increased 15-fold since the 1990s, and EcoFarming Daily cites studies showing either minimal or significantly higher herbicide use on GMO soybean farms compared with conventional ones. Both claims can be true at once: total glyphosate volume can rise even as efficiency per bushel improves, if yields grow faster than chemical use does. The industry figures measure output per bushel, while the critics’ figures measure total volume applied to fields.

For a reader asking simply whether more herbicide reaches the field each season, the volume figures from the Non-GMO Project and EcoFarming Daily are the more directly relevant number, since they answer that specific question rather than a production-efficiency question.

What Do the Efficiency Numbers Show in Practice?

The 43 percent and 47 percent figures from Soy Connection describe change since 1980, not a single year’s snapshot, and they measure resources used per bushel produced rather than resources used per acre planted.

A field today can require the same or more herbicide overall while still scoring better on these measures, because modern soybean varieties, including GMO ones, produce more bushels from the same acre than older varieties did decades ago.

Higher yields spread the same environmental cost across more food, which is why an efficiency figure can improve even while a volume figure, like the Non-GMO Project’s 15-fold glyphosate increase, moves in the opposite direction. Neither number is invented, and neither contradicts the other; they simply answer different questions about the same fields.

Frequently Asked Questions

Is Soy a GMO?

Most soy grown in the United States is genetically modified. About 90 to 95 percent of the US soybean crop carries an engineered trait, usually tolerance to the herbicide glyphosate. Soy that has not been genetically modified does exist, but it is a small share of total production and is usually labeled organic or non-GMO. That share has held steady for more than a decade, so it is unlikely to shift quickly.

Do GMO Soybeans Look or Taste Different?

No. The International Food Information Council states that GMO soybeans look the same, taste the same, and have the same nutritional profile as conventionally grown soybeans. That genetic change affects how the plant responds to herbicides, not its appearance, texture or flavor.

Is Soybean Oil Made from GMO Soybeans?

Most of it is, since 90 to 95 percent of the US soybean crop is genetically modified and a large share of that crop is crushed into oil. Soybean oil is one of the most common cooking oils in the US food supply, and unless a bottle specifically says organic or non-GMO, it almost certainly comes from genetically engineered beans. Whole soybeans sold as food, such as edamame, make up a much smaller share of the crop than oil and meal do.

When Were GMO Soybeans First Introduced?

US regulators approved the first genetically modified soybean variety, GTS 40-3-2, in 1994, and Monsanto began marketing it commercially as Roundup Ready in 1996. Other countries followed within a few years, starting with Canada in 1995. Adoption in the US had already passed 90 percent of planted acres by the early 2000s.

Are GMO Soybeans Fed to Livestock?

Yes. Just over 70 percent of U.S. grown soy becomes animal feed, more than any other single use. The rest splits between biodiesel production, at about 5 percent, and human food, at roughly 25 percent, mostly as processed oils, meals and starches, with only a small portion reaching shoppers as whole beans.

Major health authorities consider GMO soybeans as safe to eat as conventional soy. Readers who want to avoid GMO soy specifically should look for organic or non-GMO verified labels on oil, meal and packaged food, since the default soybean supply chain in the US traces back to a genetically engineered plant.

References

• Agricultural Biotechnology, U.S. Food and Drug Administration
• The GMO High-Risk List: Soybeans, The Non-GMO Project
• Genetically modified soybean, Wikipedia
• Effects of genetically modified soybean on physiological variables and gut microbiota of Sprague-Dawley rats – PMC, PMC
• The Facts About Bioengineered Crops, Soy Connection
• Beans and Biotech: Why Soybeans Are the Stars of Genetically Modified Foods, International Food Information Council
• Are GMO Soybeans the Way to Go?, EcoFarmingDaily.com

Sources read in September 2026.