The Fresh Produce Consortium (FPC) criticised the "plethora of confusing claims about green credentials" in response to the document from the Food Ethics Council.
What Should Supermarkets Do About Seasonal Food? looked at claims by retailers, campaigners and the Government on the environmental impact of seasonal fresh produce.
The report highlighted analysis suggesting that "eating fresh produce that is in season represents the lowest environmental impact".
However, the study added that other differences in production, transport and storage could outweigh seasonal effect.
An FPC spokesman said: "There's a lot of debate on eating in season and it tends to be defined as British or local. We are saying in season can mean globally sourced."
Chief executive Nigel Jenney warned against implying that produce grown indoors, imported or stored may not be as responsible towards the environment.
Fruit and vegetables could be enjoyed in season throughout the year thanks to our global market, he said. Around 60 per cent of fruit and vegetables are imported.