The study compared two meals using readily available ingredients, a healthy modern meal and a Palaeolithic age-inspired meal, so called because its composition mirrors a range of foods our ancestors would have had easy access to. Both contained the same amount of protein, fat, carbohydrates and calories but crucially the second one incorporated a broader range of plant-based foods. These included nuts and spices such as cinnamon in addition to fresh fruit and vegetables.
The metabolism of the volunteers was monitored three hours after eating and those that consumed the modified meal felt much fuller. Furthermore, results showed they had significantly higher levels of PYY, a hormone that tells the brain we have had enough to eat.
Explanatory reasons for the results include that the Palaeolithic-inspired meal had a low energy density resulting in a physically bigger meal for the same amount of calories than the modern meal. This could account for the increased satiety levels. The meal was also designed using plant-based ingredients chosen to be both high in fibre and rich in phytonutrients.
Professor Mark Berry, Senior Scientist at Unilever who is leading the research said: "Initial findings from our study suggest we might do well to get back to basics and eat a diet for which our bodies have evolved. With its mix of lean meat, fresh fish and a very broad variety of plant-based foods, our ancient ancestors' diet was different from what most of us consume today. Furthermore, the human genome has not had time to respond to radical recent changes in our diet and therefore human physiology is at odds with the vast majority of modern diets."
Professor Berry added: "The great thing is we didn't have to invent a time machine to do this study - all the ingredients needed for the Palaeolithic-meal could be readily purchased."
Further potential benefits of the Palaeolithic-inspired meal include a reduced risk of type 2 diabetes and a report on the findings is expected later this year.
Professor Gary Frost from Imperial College London said the initial findings could have other profound benefits: "Up to now surgery has often been the only viable solution to tackle chronic obesity but this research has exciting future possibilities of opening up a genuine alternative to gastric surgery. The observation that Palaeolithic diet leads to an increase in PYY raises the possibility of designing a diet that would act as a sort of nutritional bypass."
Dr Frances Bligh, Lead Scientist at Unilever said the team now plan to work with academic colleagues to investigate some of these effects further. "We want to see if the findings could be applied to foods of the future."
