Dec. 18, 2014 -- There's no proof that the popular paleo (Paleolithic) diet actually matches what early humans ate, a new study says.
The diet -- heavy in meat, fish and vegetables and light in grain products and processed food -- is supposed to be similar to how humans' ancestors ate between 10,000 and 2.5 million years ago, ABC News reported.
But there is little evidence that early humans consumed a specialized diet or regarded any one food group as especially important, according to study author Ken Sayers, an anthropologist at Georgia State University.
"Whatever angle you chose to look at the diets of our early ancestors, it's hard to pinpoint any one particular feeding strategy," he told ABC News.
In fact, it's more likely they were opportunistic feeders, Sayers said.
The study was published in the Quarterly Review of Biology.