‘Cherry pickers’ under fire
At the Western Australian Agribusiness Crop Updates, prominent science commentator Dr Karl Kruszelnicki urged growers and the grains industry generally to be vigilant against pressure groups that “cherry pick” research data to push unscientific agendas.
Dr Karl, more widely known as a broadcaster, holds multiple degrees and postdoctorate qualifications in disciplines as diverse as medicine, physics, mathematics, biomedical engineering and astrophysics.
In a presentation titled ‘The Palaeolithic anti-grain diet is not real but climate change is’ he said too many vested interests were distorting information and setting up potentially damaging scenarios for sectors such as agriculture and the community generally.
Dr Karl took particular aim at the promoters of the ‘Palaeolithic diet’, which he said was simply ignoring key elements of human evolution and biology.
The ‘Paleo diet’ claims that humans had fully evolved before the advent of agriculture, therefore foods such as dairy, grains, legumes or processed oils are detrimental.
“There are a few problems with this. Humans have actually done a lot of evolving in the past 12,000 years, plus we can’t eat what our Palaeolithic ancestors ate because a lot of it isn’t around any more,” Dr Karl said.
He said anthropological and archaeological studies, including examination of prehistoric fireplaces, middens, teeth and actual meal preparation tools, showed our ancestors had diverse diets depending on where they lived: “While the Inuit of the Arctic have a diet that is 99 per cent meat, the !Kung of Africa eat around 12 per cent meat. That’s a huge range.”
Some humans also evolved to be able to drink milk as adults, others evolved extra copies of the amylase enzyme to more easily digest starches and some, such as the Japanese, evolved special bacteria in their gut to digest seaweed. Added to this is evidence that some humans were eating grains and legumes as far back as 30,000 years ago.
Dr Karl also pointed out that many foods promoted as representing a Paleo diet did not exist during that period. Today’s corn was then a straggly grass, tomatoes used to be tiny berries and bananas were mostly filled with seeds until a recent mutation: “We have transformed the meat and plant species we eat through millennia of artificial selection and evolution. For example, cabbage, broccoli, brussels sprouts, cauliflower and kale are each wildly different cultivars of one single species, Brassica oleracea.”
Dr Karl said the Paleo diet runs counter to every dietary recommendation worldwide, adding that it tends to be promoted by celebrity nutritionists and chefs, not formally trained nutritionists and dietitians.
He also spent considerable time explaining climate change and the evidence-based science behind it.