The debate goes back and forth, but chalk one up for the “organic is better for you” side. A study conducted at the University of Barcelona (UB) found that tomatoes grown under organic conditions contained higher levels of healthful phenolic compounds than conventional tomatoes.

For the UB research team, this latest study involved getting to the heart of a matter they’d already investigated. The Natural Antioxidant Group, led by Rosa M. Lamuela, had demonstrated in prior studies that organic tomato juice and ketchup have higher polyphenol content than the same products derived from conventionally grown tomatoes. Phenols are important because as antioxidants, they have been linked to benefits for cardiovascular health, as well as reduced risk of some degenerative diseases and cancers. The researchers studied the Daniela tomato varietyusing liquid chromatography and mass spectrometry to identify 34 different phenolic compounds.

The differences found between organic and conventional products can be explained by the type of fertilizer used. “Organic farming doesn’t use nitrogenous fertilizers. As a result, plants respond by activating their own defense mechanisms, increasing the levels of all antioxidants,” lead author Anna Vallverdú-Queralt said of the study (published in the Journal of Agricultural and Food Chemistry). The more stress placed on a plant, the more polyphenols that get produced.

The researchers want to conduct a study comparing the health of humans that eat either organic or conventional tomatoes.

Published in WholeFoods Magazine, August 2012