The trendy Paleo diet, which claims we’d be healthier if we ate more like our Stone Age ancestors, is based on a misunderstanding of how evolution works, according to a leading evolutionary biologist.
Professor Marlene Zuk from the University of Minnesota says some people look to evolutionary heritage to make decisions about diet, but those decisions are not always based on the way evolution really works.
Professor Zuk is presenting her research to around 600 of the country’s nutrition science experts at the Dietitians Association of Australia (DAA) National Conference in Perth this week (13-16 May).
“The Paleo diet is based on the idea that human genetics have not changed or evolved over the past 10,000 years, since the time before the use of agriculture,” Prof Zuk says.
“But plenty of evidence exists that our genes have changed over the last few thousand years, and these changes mean we can eat foods our hunter-gatherer ancestors could not. The ability to digest milk is an example of this.”
She says several African, European and Middle Eastern populations have evolved to tolerate lactose in milk, which contradicts a primary premise of the Paleo diet.
Prof Zuk adds that little is known about the actual foods eaten by our Paleolithic ancestors and that they probably ate many different diets depending on where they lived, so today’s Paleo diet likely does not reflect ancient eating patterns.
The modern-day Paleo diet promotes mostly meat, fish, vegetables, nuts, animal fats and coconut oil, while foods that come from agriculture, including all grains, legumes, dairy foods and processed foods are avoided, and fruit is limited.
“Almost all of the foods available today are vastly different from the forms that our Paleolithic ancestors would have eaten, and this does not just mean ice cream, chips or even flour, but basics such as meats, fruit and vegetables.
“Trying to emulate what people ate 10,000 or 100,000 years ago is impossible,” says Prof Zuk.
“Clearly a lot of people who follow a Paleo diet are happy with it and feel like they’re healthy,” says DAA President Liz Kellett.
“But rigorous nutrition science says they’re in danger of missing out on some key nutrients that they need for long-term health.
“Following the Paleo diet you have to be so careful to make sure you get key nutrients which the diet can lack, especially fibre and calcium.”