There are 7 million species of animals on the planet and we’re the only ones of all of them who have walked away from our wild diet and created a new menu.
The technical term for phytonutrients is polyphenols. They are substances produced by plants, a lot of them for self-defense. Twenty-five thousand different ones have been identified. Vitamins E, C, and beta-carotene are examples. Many of them are potent antioxidants, while some don't have antioxidant activity but boost our own antioxidant defense system. Others are involved in communication between cells, many affect gene expression, and others have detoxifying functions.
I have come across a dozen studies that shows that you get more phytonutrients and more minerals and vitamins from organic, but there are also studies that show that plants raised conventionally have more phytonutrients. And they trace it to the amount of nitrogen in the fertilizer used on conventional farms. The gold standard is choosing the most nutritious varieties and raising them organically, and that's what I recommend.