The research also found two-thirds of the land needed to produce the UK's food is located abroad - much of which is from the EU, South America and South East Asia.
This figure has increased by 23% in the past 30 years because of higher demand, while associated CO2 emissions have risen by 15% in the same period.
The report acknowledges the positive effect on economic development, but researchers warned that this has "implications" for national food security.
The scientists said an increasing reliance on foreign food could make it harder for Britain to become self-sufficient.
"Producing sufficient, healthy food for a growing world population amid a changing climate is a major challenge for the 21st century," the study said.
"These results imply that the UK is increasingly reliant on external resources."
The report comes after figures published last year from the National Farmers' Union suggested that Britain would only be able to feed 53% of its population by the mid-2040s.