In the past 5-6 years there has been a 30% increase in the growth of organic foods. This is due to the perceived notion that organic foods are healthier than regular foods. According to "Organic Facts" regular food is just as good for you as organic foods. They say there have been studies that show organic milk and tomatoes are, in fact, healthier than regular milk and tomatoes.
"Recent research conducted on organic milk has shown that it has more anti-oxidants, omega 3, CLA, and vitamins than non organic milk." "According to a 10 year study conducted by the University of California, Davis, organic tomatoes are produced in an environment that has lower nutrient supply as nitrogen-rich chemical fertilizers are not added. This leads to excessive formation of antioxidants such as quercetin (79% higher) and kaempferol (97% higher) in organic tomatoes. - Organic Facts"
If you do not already buy organic foods, this may be a reason to buy organic foods. Even though they are more expensive, the health benefits out weigh the cost.