A United States study comparing organically-grown tomatoes with conventionally-grown tomatoes has found significant health benefits in the organic produce.

The 10-year study, published in the Journal of Agriculture and Food Chemistry, showed flavonoid levels were up to 97 per cent higher when tomatoes were grown in organic soils and fertiliser applications were reduced.

Flavonoids are types of antioxidants that are thought to protect cells from molecular damage.

Biological Farmers of Australia's Scott Kinnear says it is a ground-breaking study.

"It really does send a very strong signal to policy makers, that if this research has some basis that can be extrapolated through other food groups and through other soil types and through other countries, then that's profound," he said.

"We really should be looking very closely at organic agriculture as a long-term means of ensuring better health." Byron Bay Florist