Organic VS. Conventional
Despite the conflicting information that is out there, from studies that say organic isn't any more nutritious than conventional. Some say there isn't the research (USDA). Well I found this study and think this is a good one that compares 41 studies. More are being done every day and you have to follow the money to find out where the bias of their study lays and if their methodology is well rounded.
On a personal note. Our farm was at an event last spring and a man was there testing sugar levels in store bought produce, conventional and organic with a brix refractor (measures sugar levels in plants. The higher the sugar level for a particular plant the healthier it is, on a scale of 1-10. Of course some vegetables have more sugar than others like carrots on the high end and some greens on the low end) He was showing or intended to show people the difference between the health of organic produce and conventional store produce. He tested both and found no difference. We gave him one of our onions and it registered an 8. You may ask why?
Well big corporate organic ag is the same as conventional in that they have just subplanted organic amendments and sprays for synthetic ones, but the mind set is the same. They plant in a monoculture and a monoculture is a monoculture is a monoculture whether planted organically or not still wears out the soil. The national organic rules now allows for IPM Integrated Pest Management in orgainc fields, which means in order to save a harvest from crop failure due to pest or disease they can spray. Organic produce in Mexico is allowed to be sprayed with human sewage sludge (hence the tomato scare).
Our insignificant onion registered a 8 because organic isn't about substituting substances or not spraying. It is about feeding the soil and building a healthy microbial environment that will break down the minerals and nutrients in the soil so that the plants can uptake them, plus we harvest at the nutritional peak of the plant or fruit (ripe). The best way to ensure that your food is nutritionally dense is to buy from your local sutainable, certified naturaly grown or organic farm where you can have access to the farmer to ask about their growing practices (most are honest) and most are willing to let you come and see what they are doing.
On our farm we want people to be informed about thier food, "we are what we eat" one of the most important decisions you make every day that impacts your whole family and their health so we don't have a problem answering questions, or having our customers visit. Many of our customers have health issues and allergies so we work hard to grow the best food we possibly can.