Opinion: The Illusory Truth Effect or "Snark Syndrome" is allowing people to blame poor nutrient density on farming practices rather than their personal food choices, writes Dr Jacqueline Rowarth.
The world is suffering from the Snark Syndrome.
"What I tell you three times is true," says Lewis Carroll's wonderful Bellman in The Hunting of the Snark.
It's termed the Illusory Truth Effect – the tendency to believe false information after repeated exposure.
You start to believe it because "everybody knows".
It will have greater nutrient density - the amount of a particular nutrient in a food per calorie or kilojoule consumed.
As science has not managed to do this in the past, it is unclear why anybody would think throwing more money at the non-issue will do so in the future.
There is no consistent, credible research that has been found by repeated meta-analyses and reviews which shows that food produced under different productions systems differs substantively in nutrient concentration.
The same goes for modern food compared with 50 years ago. The occasional small difference is nothing in context with the full diet.
Differences are to do with soil and climate (terroir), stage of harvesting and cultivar or breed.
There are also some differences between now and the past due to increased carbon dioxide concentration in the atmosphere – but there aren't differences between organic and conventional grown in the same year in the same soil.
Given that regenerative agriculture is part of the spectrum between organic and conventional, along with agro-ecology and conservation agriculture, why would the results be different?
Listen to Jamie Mackay interview Dr Jacqueline Rowarth on The Country below:
Note that the "no difference" is before the farm, orchard or market garden gate.
Food grown at home tastes better than the alternative because it is fresher – you harvest it at its best and eat it immediately. But the home gardener mostly cannot provide the variety of fruit and vegetables that is available all year round from the supermarket.
Once the food leaves the producer and goes to the processor and distributor, things change.
Post-harvest treatment is critical.
Snap-frozen peas frequently have more sweetness than fresh peas (unless grown at home) because they are harvested at the peak of perfection, frozen within a four-hour window of harvest, and the transport and waiting to be bought occurs when the peas are already preserved.
Processing sometimes adds components to the original product and dilutes the "nutrient density".
Potatoes contain a considerable number of nutrients. Deep-fried and salted, the value reduces. The same goes for oats turned into muesli bars with fat and sugar.
The debate about milk and meat is slightly different. Within a species, breed does make a difference.
Milk from Jersey cows is higher fat than that from Holstein Friesians. Processors in New Zealand collect the milk and blend it to ensure a consistent quality, and then meet consumer demand with low fat, high calcium, chocolate etc.
This is nothing to do with the production system of the farmer or grower but does change nutrient density.
In particular, the omega 3s are higher (up to five times) in grass-fed meat, just as they are in grass-fed milk.
If, however, you are deficient in omega 3s, switching to "grass-fed" won't make a difference to your health (particularly in New Zealand where the norm is pasture) - you will need supplements.
The suggestion that slower-growing leads to better tasting meat may well be the case overseas where hormones are given to animals to increase growth rates.
In New Zealand they are not given additional hormones; they respond to their own hormones and genetic potential, reaching weight according to food quality and quantity.
On pasture, if animals grow slowly the implication is that there is something wrong, perhaps health or food restriction (quantity and/or quality).
Further, greenhouse gases (GHG) produced per kilogram of food are increased because of the animal's maintenance costs.
GHG are an important factor when suggesting that organics, regenerative or whatever are "kinder" to the environment than conventional systems.
Again, considerable research has shown that per unit of food produced, conventional agriculture has a lower impact on the environment than any other system because yields are higher per unit of input.
Add in the effect of expanding agricultural land into what used to be forest (to cover reduced yields in non-conventional agricultural systems), and the problems are clear.
What drives food demand is mouths and there are more and more of them on the planet.
The reality is that New Zealand has superb food, produced with lower environmental impact than other countries can manage. What happens to the raw product before it reaches the consumer is a matter of consumer choice.
The Illusory Truth Effect is allowing people to blame poor nutrient density on farming practices rather than their personal food choices.
It is also encouraging the belief that a return to past production systems will cure everything.
Success would require a return to past population as well.
- Dr Jacqueline Rowarth, Adjunct Professor Lincoln University, is a farmer-elected Director of DairyNZ and Ravensdown. The analysis and conclusions are her own. jsrowarth@gmail.com