As Canadians prepare to roll out their holiday spreads, we might want to draw a little inspiration from our ancestors.
New archeological evidence suggests the modern-day diet could benefit from being more like what Homo sapiens were eating 100,000 years ago.
Dozens of stone tools found during an excavation in southeastern Africa represent the earliest evidence of human reliance on grains for sustenance, according to Julio Mercader, the University of Calgary researcher who uncovered the artifacts.
Previous evidence suggested human hunters and gatherers had been eating grains for the past 20,000 years. This new discovery has added about 80,000 years to that estimate.
"From a human-evolution point of view, it shows that the diet of Homo sapiens in the Stone Age was a little more diverse than previously thought," said Mercader, who holds the Canada Research Chair in tropical archeology. "Grains were as much a part of the diet as were underground plants and fruits."
The tools also demonstrate that human ancestors were already displaying modern, complex behaviours 100,000 years ago, he said.
"From an earlier stage, humans were starting to process foods, expand their diets and use the landscape and resources they could."
Some of the uncovered tools were used to grind the harvested grains, making them fine enough to add to other foods and drinks.
During the excavation, Mercader found traces of a grain called sorghum. Today, that gain's descendant is the primary grain consumed in sub-Saharan Africa, where it is used for flours, beverages and porridges.
Alongside the tools used for processing grains, the archeologist and his team found the Stone Age pantry was also stocked with legumes, wild oranges and tubers — further evidence these human ancestors had a "sophisticated and expanded diet," Mercader said.
Introducing grains to the human diet and developing the ability to digest them were critical steps in the evolution of modern man, Mercader said.
Though the tradition of eating grains may stretch back 100,000 years, many people still aren't getting enough in their diets these days, said Thomas Wolever, a professor of nutritional science at University of Toronto.
As part of a second-year undergraduate nutrition class, Wolever asked his 400 students, most 18 to 20 years old, to keep a journal of what foods they ate and how much of each they packed in.
"The only food that most of the class ate enough of was meat," Wolever said. "Fibre intakes are woefully low, very far from the daily requirements," he said.
Fibre intake can be boosted by eating more whole grains, Wolever said, just as our Stone Age ancestors seem to have done.
Carbohydrates provide fuel for the brain and body, and modern science indicates they may reduce risks for diabetes and cardiovascular disease.
Wolever, who has been a vegetarian for about 35 years, said his family is planning a meatless Christmas dinner. Their spread of pasta, salad, rice and bread will be full of whole grains, unlike the turkey, potatoes and pies that will be featured on many North American dining room tables next week.
"There are many ways to prepare grains — tasty ways," he said. "I think the ancient people, they had the right idea."
Mercader's findings are being published in the Dec. 18 issue of the research journal Science.