A recent study in Ireland found more antioxidant activity and higher
flavonol content in organic onions compared to conventionally grown
While it’s a relatively narrow finding, it’s significant because the
study lasted six years, which is reported as the longest-running study
of its kind. The differences in antioxidant activity and flavonol content were found to be due to different soil managemnet practices used in organic farming, such as organic fertilizer, crop rotation, and
cover crop, rather than a lack of pesticide/herbicide use.