Engineers design plants using genetically modified organisms (GMOs) to be tougher or more nutritious or to taste better. However, people have concerns over their safety, and there is much debate about the pros and cons of using GMOs.
In this article, we discuss the advantages and disadvantages of GMO crops, including their potential effects on human health and the environment.
- Manufacturers use genetic modification to give foods desirable traits.
- Potential advantages of GMO crops include:
- increased attractiveness to consumers, for example, apples and potatoes that are less likely to bruise or turn brown
- enhanced flavor
- longer shelf life and therefore less waste
- greater resistance to viruses and other diseases, which could lead to less waste and increased food security
- greater tolerance to herbicides, making it easier for farmers to control weeds
- increased nutritional value, as in golden rice, which can boost the health of people with limited access to food
- greater resistance to insects, allowing farmers to reduce pesticide use
- ability to thrive in a harsh climate, such as drought or heat
- ability to grow in salty soil
- Growing plants that are more resistant to diseases spread by insects or viruses will likely result in higher yields for farmers and a more attractive product.
All these factors contribute to lower costs for the consumer and can ensure that more people have access to quality food.
Genetically engineering foods is a relatively new practice, which means the long-term effects on safety are not yet clear.
Many concerns about the disadvantages relate to human health. Scientists have not yet shown that GMO foods are harmful to health, but research is ongoing.
There is a small risk that GMO foods can trigger an allergic reaction, but this will only happen if the genetic change triggers the production of an allergen.
For instance, if scientists combine a gene from a Brazil nut with a soybean, there is a slight chance that a person with a nut allergy could have an allergic reaction to products made with the soybean.
The World Health Organization (WHO)Trusted Source discourages genetic engineers from using DNA from allergens unless they can prove that the gene itself does not cause the problem.
Scientists assess the likelihood of GMO foods causing an allergic reaction in humans before a product reaches the market, and can prevent its launch if necessary.
There have been concerns that eating GMO foods can contribute to the development of cancer by raising levels of potentially carcinogenic substances in the body.
The American Cancer Society states there is no evidence that currently available GMO foods either increase or reduce the risk of cancer.
While cancer rates have changed over time in the U.S., there is no evidence that these changes coincide with the introduction of GMO foods. If there is a link, it could take several more years before a trend emerges.
Some GMOs contain changes that make them resistant to certain antibiotics. In theory, the genes from these plants could enter humans or animals when they eat them. As a result, the person or animal could also develop antibiotic resistance.
The likelihood of this happening is very small, but the WHO and other health authorities have guidelines in place to prevent it.
Changes in human DNA
In 2009, some food scientists noted that food DNA can survive as far as the gut, and there have been concerns that this could affect the immune system.
Some people have also raised fears that eating GMO food could lead to genetic changes in humans. However, most of the DNA in food — whether GMO or not — either is destroyed by cooking or breaks down before it reaches the large intestine.
Small fragments of DNA from food can and do enter the bloodstream and body organs, but there is no evidence that they have any impact on genetic makeup or human health.
Toxicity for body organs
In 2009, some researchers suggested that GMO foods might impact the liver, kidney, pancreas, and reproductive system. They did not have evidence to confirm this and called for further studies.
The use of GMO crops may even reduce the risk of toxicity from some substances, as farmers can avoid using pesticides that have been harmful in the past.
Are GMO foods good or bad for the environment?
Climate change and severe weather events are disrupting food production and supply. GMO foods could help maintain supplies in the face of changing environmental conditions and a growing population.
- Genetically modifying some foods could make them:
- easier to store and transport
- less prone to waste due to disease and aging
- more likely to grow in areas with poor quality soil
- higher in nutrients
Also, a 2022 study suggests GMO foods could help slow climate change by reducing greenhouse gases.
Environmental concerns include:
- the risk of outcrossing, where genes from GMO foods pass into wild plants and other crops
- a negative impact on insects and other species
- reduction in other plant types, leading to a loss of biodiversity
- The risks will vary depending on local conditions.