Making sure GM food is safe to eat
Friday 14 February 2003
Find out how GM food is checked for safety and assessed for sale.
Please note: content for this GM website was produced for the 2003 GM food debate. For the most up-to-date information, see our eatwell website or the GM and novel foods section of food.gov.uk. You can also find out more about GM foods on the International Service for the Acquisition of Agri-biotech Applications (ISAAA) website.
What happens when people eat GM food?
Human beings have always eaten plants and animals, which means we have always eaten their DNA without it causing any health problems. Given that GM DNA is still DNA, eating it should not pose any greater risk than eating unmodified DNA. Indeed, no one has ever been reported as suffering from illness because the food they had eaten had been genetically modified.
When someone eats GM food it is processed in the same way as non-GM food. When we eat any food, our digestive systems break down the tissue, the proteins and the DNA in the food. The DNA in GM food has the same structure as non-GM DNA and is broken down in the same way. Most DNA that is consumed, whether GM or not, is broken down in our stomachs and intestines.
Sometimes, the DNA from the food we eat isn't broken down. However, it is unlikely that this DNA will become part of our genetic material by passing into our cells – any non-human DNA should simply be broken down in the cell.
Antibiotic-resistant marker genes
During the process of genetic modification, marker genes are used to check whether particular cells have taken up the modified gene. Antibiotic-resistant marker genes are one type of marker gene. If a cell is resistant to the particular antibiotic, this shows that the cell has taken up the modified gene. Some people have suggested that antibiotic-resistant marker genes could be transferred into the bacteria in our gut, along with the resistance to the particular antibiotic. If this happened, the particular antibiotic, if prescribed to treat an infection, would not work in that person.
The Advisory Committee on Novel Foods and Processes (ACNFP) is an independent scientific committee that advises the Food Standards Agency. In 1996, when the first GM maize was approved as a food, the ACNFP raised the concern that antibiotic resistance marker genes might be transferred from GM plants to the bacteria in our digestive systems. At that time, the ACNFP concluded that there was a low risk of this happening. Since then, further research has shown that the risk of transfer is even lower than originally thought.
Are GM foods assessed for safety?
For more information about safety assessments, see the Evaluating GM foods section of food.gov.uk.