'Disease risk'
The study found that 86% of the dishes would be labelled as red for fat levels under the Food Standards Agency (FSA) traffic light system.
It found that more than 75% would also be labelled as red for salt levels.
Nutrition expert Denise Thomas, of Portsmouth Hospitals Trust, told Newsbeat some takeaway food had "dangerous" levels of fat.
"It's harmful because, most of the time, people would have a kebab in addition to two other meals," she said.
"If you had a normal two meals and then you're doing that, it's a progressive thing."
She added: "You're going to be gaining weight because there's so much fat.
"This will clog the arteries hence increasing the risk of heart disease."
The 148 samples, which also included Chinese and Indian meals, pizzas and fish and chips, were taken from eight different local authority areas in the south of England.