People have been eating 'genetically-modified' food for a long time, it just wasn't a hot-button topic. It's not like these foods are being 'created' in some scientific production line laboratory. They're being raised on farms like they always were. The farmers are just getting smarter.
Most of these so-called 'modifications' are nothing more than modernized versions of selective-breeding and plant grafting. Just because we're able to manipulate cells on a microscopic level, that doesn't make them inherently 'bad' for us to ingest. The basic components are still the same, we're just learning how to manage the inherited genetic traits more efficiently, so it's much less of a 'crap shoot' than in the past.
Human beings are pretty diversely enabled when it comes to ingesting nutrients. There are some concerns that are valid when it comes to growth hormones and such, but concerns about 'Franken-foods' are simply over-hyped media fear-mongering. You're not going to grow a third eye from eating genetically-modified food. It doesn't modify your existing DNA. It's just food.