Why Eat Organic?
You can dramatically increase nutrient levels by choosing organic—called bio in some countries. Besides having fewer pesticides, organically grown foods have more nutrients than those grown conventionally with chemicals. I've covered the topic of organic dairy and meat in the page To Moo or Not to Moo? This section is for the fruits and veggies.
A survey by the Journal of Alternative and Complementary Medicine compared the nutrient content of organic and conventional crops . Organic crops contained significantly more vitamin C, iron, magnesium, and phosphorus. There was a higher content of nutritionally significant minerals found in the organic crops. They contained far fewer heavy metals than conventional crops and heavy metals are very toxic to your body.
The scientists concluded, “There appear to be genuine differences in the nutrient content of organic and conventional crops.”
Typically the more fragile the fruit or vegetable, the more often it has been coated with pesticides. The following list of foods are the most heavily sprayed in conventional farming. The Environmental Working Group, an American nonprofit that specializes in research and advocacy about toxic chemicals in agriculture, calls them the Dirty Dozen. Whenever possible, these are the most important produce foods to purchase from an organic source. The EWG updates this list annually.
2019 Dirty Dozen
Tomatoes and cherry tomatoes
+ special concern foods: imported snap peas, lettuce, blueberries and hot peppers, which are found to contain traces of highly toxic pesticides.
Fortunately, there is also a bright side. The EWG has kindly put together the Clean Fifteen, which are the safest foods to buy conventionally, as they contain the least amount of pesticides.
Sweet Peas Frozen
*some sweet corn and papaya sold in the US is produced from genetically modified seeds. Buy organic if you wish to avoid GMOs.
 V. Worthington, “Nutritional quality of organic versus conventional
fruits, vegetables, and grains,” Journal of Alternative and Complementary
Medicine 7, no. 2 (April 2001): 161–73.