Almost 70% of adults over the age of 20 in the US are overweight, with 35% considered clinically obese. These worrying stats point to a chronic problem in the modern-day diet of many people across the globe — life expectancy is starting to drop in certain areas for the first time in decades. The need for health education has never been greater - is it possible that a look back at our ancestors could be the answer? Carry on reading to discover interesting facts about the ancient human diet that may suggest how we humans should be eating today.
Meat has played a major role in the evolution of the human diet. In fact, some scientists believe that our ancestors' consumption of meat was crucial to the development of their larger brains around 2 million years ago. After they started to eat calorie-rich meat and bone marrow from the carcasses of large mammals, many researchers believe that our ancestors were able to take in enough excess energy to fuel the growth of these larger brains.
The shift to a higher-quality diet, with less bulky plant fibre than previously consumed, meant that our ancestors were able to develop smaller guts. The energy saved on digestion in these smaller guts meant more energy for the ever-expanding brain. When resting, the brain requires a staggering 20% of a human's energy, compared to just 8% for an ape's brain.
While our hunter-gather ancestors likely craved meat over other sources of sustenance, it was the 'gather' element of feeding expeditions which kept them going day-to-day. Research conducted on fossils suggests that humans may have been eating grains and tubers for at least 100,000 years, and it's well documented that plants and nuts were a regular source of nutrition for our prehistoric grandparents.
The diverse nature of our ancestors' diet goes hand in hand with the active existences they led. Because survival was their primary instinct, taking in whatever sources of energy they could find whilst on the move made for the kind of active, healthy lifestyles that we consider so important today.
Of course, our early ancestors didn't cook the meat they consumed. Raw meat requires more energy to process, whereas the advent of cooking - somewhere between 1.8 million and 400,000 years ago - meant that our bodies had less to break down from the meats that were essentially predigested in the cooking process. The problem with this evolution is that humans have become so adept at processing foods, we're now seeing huge swathes of the population consuming more calories than they burn in a day.
Our early ancestors certainly consumed meat, but this specific area of their diet is often overplayed due to the butchered bones of wild animals being so well preserved at excavation sites. In fact, it's thought that early humans collected over 50 types of plants - either eating them as vegetables or harvesting fruits, nuts, seeds, and underground stems.