GMO Insulin: What You Need to Know

It's been four decades since the first GMO insulin, a synthetic version of the human hormone insulin, was produced. Today, man-made insulin comes in many forms, says the American Diabetes Association (ADA). But is it safe?

Insulin is a protein made in the pancreas that helps your body process sugar, turning the sugar in your blood, known as glucose, into the energy your cells need to function. However, not everyone's body produces the needed amount of insulin.

For instance, if you have type 1 diabetes, your body can't make insulin so you need insulin from another source to survive, explains the ADA. If you have type 2 diabetes, your body may eventually have trouble making insulin. If this happens, insulin from another source may be needed.

Originally, scientists and doctors recommended fasting and calorie-restrictive diets for people with diabetes. Life expectancy was not long. Then came the discovery of insulin in 1922. At first, those with diabetes were given insulin from pork (porcine) or cow (bovine) sources, says Rohit Moghe, PharmD, MSPH, a spokesperson for the American Association of Diabetes Educators. The insulin was extracted from the pancreas of those animals.

Over time, though, the human body recognized that insulin from animals was not a human-based protein. This made it hard for some people to use insulin from pigs or cows, Moghe says, and eventually led to the development of genetically modified insulin — called GMO insulin, genetically engineered insulin, synthetic insulin, human insulin or recombinant DNA insulin.

The first GMO insulin product developed and approved was Humulin, which was licensed for human use in 1982. A man-made insulin product, Humulin replaces the insulin the body would normally make on its own.

Read more: High Insulin Levels: Causes, Symptoms and Treatment

Genetically engineered insulin is made from yeast or a bacteria such as E__scherichia coli (E coli), according to the YourGenome.org site produced by genomics-based researchers in the United Kingdom. In this process, a small piece of DNA, called a plasmid, is removed from the bacteria or yeast cell. The gene for human insulin is then inserted in the plasmid. This is considered genetic modification.

The genetically modified plasmid becomes part of a new bacteria or yeast cell. It is this cell that starts to make insulin.

"This form of insulin could then be replicated, mass-produced and altered to make insulin to be injected around mealtime or formulated in a way that has an extended duration of action," Moghe says. "This has made managing diabetes easier because there are now insulins that people with diabetes can use right before they eat or when they start to eat. They now don't need to take insulin 30 or 45 minutes before a meal, which was once the only option."

Not only is GMO insulin safe, he says, but it's easier to make on a large scale than porcine or bovine insulin. And another benefit of using GMO insulin is that it doesn't come from another species. The human body is less likely to have side effects caused by insulin if it's not from animal sources.

The genetic modification of insulin also has allowed larger production of insulin, which helps to avoid the health risks associated with a lack of insulin in people with diabetes. Without the mass production of insulin, even death could occur in those who rely on it to survive.

Also, genetically engineered insulin is made using a sterile process. When insulin is extracted from a bovine or porcine source, the process is not always as clean, Moghe says. GMO insulin is vegan, whereas insulin from an animal source is not.

Read more: Disadvantages of Genetically Modified Food

In fact, insulin from animal sources is no longer available in the U.S. Beef insulin for use by humans was stopped in 1998, and pork insulin was discontinued in 2006, according to the U.S. Food and Drug Administration.

Recent advances in the continued development of GMO insulin have shown promise, according to an August 2019 editorial in the journal Future Medicinal Chemistry. One advantage is its improved ability to help manage episodes of high blood sugar (hyperglycemia) in people with diabetes. In addition, advanced production systems for GMO insulin have offered significant benefits for people with diabetes, allowing for high-capacity, low-cost production of insulin for those who are allergic to animal-based insulin.