The question of GMO food safety comes up all the time, and because I am a public scientist it has been something I’ve studied for decades. Modern technologies have tremendous potential to do good things for farmers, the environment, the needy, and food enthusiasts — but only if they result in foods that are perfectly safe to eat. I’m extremely concerned about food safety, both as someone raising a teenager and as a rapidly aging athlete doing everything I can to keep my ever-diminishing edge. That said, I don’t worry about consuming GMO foods.

Quite to the contrary, I have a lot of confidence in these products. Maybe it is because I understand the technology that brought them about. Humans have done a lot to change plants from their natural state, converting what were rather useless weeds and bushes to productive food crops. These improvements were performed by breeding and selection, that is, crossing plants and cultivating the best traits of each generation. This process is certainly genetic modification in the truest sense of the term, as much genetic information is mixed in ways we can’t easily predict or understand. Plant breeders are scientists who shuffle the genetic deck to find the rare outcomes that gave us our most useful varieties.

In the 1980s scientists moved one gene between very different organisms. The gene was the human gene for insulin and it was moved into bacteria so they would produce 100% human insulin for medical applications. This was a good example of what scientists call a “transgene,” the scientifically precise term for “GMO,” which seems to mean something different to different people.

In the 1990s plants were engineered with a single trait transferred from a bacterium to a plant. One example comes from a pesticide used for organic produce production. The pesticide is a bacterium that produces a compound that is toxic to caterpillars. The gene encoding the anti-caterpillar compound was cut-and-pasted from the bacterium into the plant, allowing the plant to manufacture its own insect protection. The result was that the need for insecticide application on corn and cotton was cut by much more than half.

Many were wary that a compound that harms caterpillars was in their food, and that’s understandable at first. However, we need to remember that plants produce many compounds targeted at insect pests, mostly because they have to defend themselves from pest pressures. The anti-caterpillar compound here is a protein that selectively targets a mechanism only in caterpillars. It does not work on most other insects and certainly is safe on birds and mammals, including humans. In us, the protein is broken down just like the other 40,000 plant proteins we consume. To the caterpillar it’s poison, to humans it is nutrition — in the same way that chocolate, grapes, and raisins are toxic for a dog but not harmful to people.