Research finds bacon is more ‘green’ than a head of lettuce
Gentle souls who want to save the planet by eating vegetables have been dealt a blow by no less an authority than Scientific American.
The magazine recently published some inconvenient scientific findings. Inconvenient, that is, to vegetarians.
The article even throws doubt on the idea that higher levels of atmospheric carbon dioxide are the cause of the planet warming, and changing the climate for the worse. What next? It is an outrage! Eat lettuce and hasten the demise of the planet. Really, the extent to which oil companies will go!
Leaving aside their climate cousins for the moment, vegetarians everywhere have been warned that far from a plain lettuce salad being both healthy for humans, and at the same time protecting the planet, this favourite rabbit food emits copious quantities of carbon dioxide – that poisonous gas we all exhale 24/7.
It gets worse. Production of lettuce leads to the emission of three times more carbon dioxide than – wait for it – the production of bacon.
If that weren’t shocking enough, the scientists say that eating more fruits, vegetables, dairy and seafood is more harmful to the environment because they use up resources while growing, and when brought to supermarket shelves emit more greenhouse gases than other foods.
“Lots of common vegetables require more resources per calorie than you would think. Eggplant, celery and cucumbers look particularly bad when compared with pork or chicken,” said Christopher Hendrickson, the Hamerschlag University professor of civil and environmental engineering at the Carnegie Mellon University in the US.
He studied the food supply chain. He wanted to see if fat people (in the US obesity is epidemic) and their diet was affecting the environment – energy use, water use and greenhouse gas emissions, and so on. The results showed that, indeed, eating less had a positive effect on the environment, led to less energy and water use and reduced the greenhouse gas emissions of the food chain by about 10 percent. Thin people – good; er… fat people – bad. A very politically incorrect implication.
However, it gets worse. The study showed that a diet of fruits, vegetables, dairy and seafood, had a negative environmental impact. Energy use jumped by more than a third, water use went up 10 percent and deadly greenhouse gas emissions rose by an extra 6 percent. The Scientific American report notes that the comparisons are calorie-to-calorie.
A reason for the research was to test the validity of the dietary recommendations made by the US Department of Agriculture. These apparently guide what is provided nationally in US state schools. At the moment, the guidelines advocate fruit, vegetables, dairy and seafood, and abjure processed food high in sugar.
Good and bad
Professor Paul Fischbeck, one of the team that carried out the study, said: “You cannot… assume any vegetarian diet is going to have a low impact on the environment… You can’t treat all fruits and veggies as good for the environment.”
To the relief of mothers everywhere, the professor does not say all vegetables have high carbon footprints. Onions, okra, carrots, broccoli and Brussels sprouts are fine. Just the stuff all children love.
Martin Heller, a research specialist with the Centre for Sustainable Systems at the University of Michigan, has drawn similar conclusions. If Americans shifted to following the Agriculture Department’s dietary guidelines, they would consume less meat – good for emissions; but would drink more milk – bad for emissions.
Switching to a lacto-ova vegetarian diet (presumably milk and eggs) would result in a 33 percent decrease in emissions.
But on the bacon-versus-lettuce greenhouse gas emissions showdown, Heller called the comparison “ridiculous”.
“We don’t eat lettuce for its calories,” he said, adding that was why in his food analyses he preferred to do assessments of full diets. If you want to be kind to Earth and yourself, Heller suggests cutting out meat. In the new analysis, beef was three-and-a-half times more environmentally intensive than pork. Overall, livestock accounts for more gas emissions than motor vehicles.
So what to do (if you can afford to choose what you eat)? Adopt a more plant-based diet with plenty of fruits, vegetables, whole grains and legumes.
Simple, yes? Er, no.
Back to Fischbeck (the lettuce man). He admits that although it seems counterintuitive, the best diet for the environment would be terrible for a person’s health.
“If you totally forget health, which diet would have the best impact on the environment?” Fischbeck asked. “You’d eat a lot more fats and sugars.”
Now, that is something for dietitians to fight about.
* Keith Bryer is a retired communications consultant.
** The views expressed here do not necessarily reflect those of Independent Media.