An independent review commissioned by the Food Standards Agency (FSA) found there were no important differences between organic and conventionally-produced food.
The conclusion was reached after a team of researchers at the London School of Hygiene & Tropical Medicine (LSHTM) reviewed all papers published over the last 50 years relating to nutrient content and health differences between the two kinds of produce.
Organic farming, which focuses on protecting wildlife and the enviroment, means no artificial chemical fertilisers are used, pesticide use is restricted and animals are expected to be free range.
It has become increasingly popular in recent years, with supermarkets offering organic options on many items.
But the paper reporting the results of the review of nutritional differences - published by the American Journal of Clinical Nutrition - appears to cast doubt on the potential benefits to people's health from the method.
Principal author Dr Alan Dangour, of the LSHTM's nutrition and public health intervention research unit, said: "A small number of differences in nutrient content were found to exist between organically and conventionally-produced crops and livestock, but these are unlikely to be of any public health relevance.
"Our review indicates that there is currently no evidence to support the selection of organically over conventionally-produced foods on the basis of nutritional superiority."
The FSA said it supported consumer choice and was neither pro nor anti organic food, recognising there were many reasons why people chose to eat it.
Gill Fine, FSA director of consumer choice and dietary health, said: "Ensuring people have accurate information is absolutely essential in allowing us all to make informed choices about the food we eat."