William Leonard has conducted extensive research on the
diets and ways of prehistoric populations. A paper on his research will be
presented at the annual meeting of the American Association for the Advancement
of Science (AAAS).
The research shows that the transition from subsistence to a
modern, sedentary lifestyle has created energy imbalances that have increased
rapidly - evolutionarily speaking - in recent years and now play a major role
Over the last 25 years, evolutionary perspectives on human
dietary consumption and nutritional health have received greater attention
among both anthropologists and nutritional scientists. Humans have evolved
distinctive nutritional characteristics associated with the high metabolic
costs of our large brains.
Too much food readily
“The evolution of larger hominid brain size necessitated the
development of foraging strategies that both provided high quality foods and
required larger ranges and activity budgets,” Leonard said.
“Over time, human subsistence strategies have become more
efficient in obtaining energy with minimal time and effort. Today, populations
of the industrialised world live in environments characterised by low levels of
energy expenditure and abundant food supplies contributing to growing rates of
Leonard’s research has focused on biological anthropology
and the adaptability, nutrition and growth and development of people in South
America, Siberia and the United States. He has extensive field experience and
has travelled the world to conduct research.
hunter-gatherers put to test
In October 2011, the Discovery Channel aired “I Caveman.”
Leonard was a consultant on the programme, which examined how well modern-day
humans could adapt to a traditional hunting and gathering way of life in
high-altitude Colorado. He evaluated changes in body weight and health status
in the participants over the course of the experiment.
The 10 participants all lost weight, experienced significant
improvements in blood pressure, cholesterol and blood glucose levels, while
following a typical Paleolithic lifestyle-consuming a diet of game, fish and
wild plant foods.