A recent review of controlled animal feeding trials found significant improvements in the health of animals given organic feed, and concluded:

"Reproductive health [and] incidence and recovery from illness are sensitive measures of health status and should be given appropriate weight. Taking all of this into account, the available data are very strong with regard to the health benefits of organic feed and food."

Similar tests with humans are problematic, though evidence is emerging here too. An early observational study revealed that boarding-school students eating predominantly organically for three years  experienced a "very marked decline" in colds and influenza, more rapid convalescence, excellent health generally, fewer sports injuries, a greater resilience to fractures and sprains, clear and healthy skin, and improved dental health.

A recent Danish organic human three-week feeding trail with 16 subjects found significantly higher concentrations of quercetin (an antioxidant flavonoid) not only in the organic diets but also in the urine of those eating organically, confirming increased absorption and systemic circulation.