It appears that while organic foods may offer some advantages (higher levels of phosphorus and antioxidant phenols), they offer no nutritional edge over conventional produce.
This is supported by a Stanford meta-analysis of 237 studies conducted over four decades which concluded that most nutrient levels are not any higher in organic produce or meats.
Although organic fruits and vegetables had lower pesticide levels, they were not pesticide-free: 7% had detectable pesticide residue, likely from drift, compared to 38% for conventional produce, whose levels were almost always under official safety limits.
Organic produce was no less likely to be contaminated by dangerous bacteria, such as E. coli. Although organic meat had much lower levels of antibiotic-resistant bacteria, scientists noted that these wouldn’t survive proper cooking.
Organic produce did have higher levels of phosphorus and antioxidant phenols, while organic milk was higher in omega-3s. Reviewers acknowledged that people go organic for reasons other than nutrition, adding, “Those are perfectly valid.” – Annals of Internal Medicine