Genetically modified foods are crop plants that have been modified in a laboratory to enhance desired traits or improve nutritional content. Genetic engineering can create plants with exact desired traits rapidly and accurately, compared to conventional breeding methods. GM foods were first introduced in the early 1990s, with soybean, corn, canola, and cotton seed oil being common plant products. Genetically modified foods are controversial, as they provide benefits but also pose risks to human and environmental health that require further study before continued integration worldwide. Potential benefits include economic gains and increased yields, while risks include harmful human health effects and increased reliance on herbicides.