求翻译：世界上许多国家都在进行转基因食品的研究工作,经研究表明，通过批准的转基因食品往往比普通食品更有营养，更安全.好处一：对健康有保障;好处二：拥有我们自身不能合成的营养素;好处三：减少了农药残留。不利方面.任何一项新的科学技术的应用都有它的两面性。转基因食品也同样.一，造成基因污染。二，有些转基因生物产品可能含有有毒物质和过敏源，会对人体健康产生不利影响，严重的甚至可以致癌或导致某些遗传疾病。是什么意思？

Genetically modified food in many countries in the world of research, studies have shown that approved GM foods than ordinary foods more nutritious, safer. benefits: health protection benefits II: synthesis of nutrients we cannot itself; advantage three: reducing pesticide residues. Downside. any application for a new science and technology has its two sides. Genetically modified foods too., cause genetic pollution. Second, some GMO and allergen products may contain toxic substances, will have an adverse effect on human health, carcinogenic or can even lead to some serious genetic disease.