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Week Eighteen - Supermarket Swap

Save 643 kilograms CO2e per person per year

· Weekly experiments


- What's your superpower today?

My preschooler

- I'm the baby bunny that never grows up. I eat things that are bad for the world and make them go away.

It's a climate emergency and the carbon bomb has landed

The Ethical Omnivore

In the absence of a carbon-ivorous bunny that will save the planet, it's hard to beat Michael Pollan's rules for the ethical omnivore. He advised us to eat food, not too much, mostly plants.

Pollan published that over ten years ago. I've just run eight weeks of food experiments to find he was right.

What food experiments did I try?

At the start of this project, my food generated just over a tonne of carbon dioxide and equivalent emissions (CO2e) each year. I compared this with an average Australian family, the Molloys, who participated in a photographic study called 'Hungry Planet - What the World Eats'. On paper, the Molloy diet generates around 1.4 tonnes CO2e per person per year. Indirect embedded emissions from food waste generated another 350 kilograms CO2e for me and 480 kilograms CO2e for the Molloys each year. I was sure I could cut down and I had a good idea of what would work.

I was wrong.

What failed?

I tried 5:2 fasting by eating less than 2500 kilojoules on two days. That only shaved 50 kilograms CO2e from my annual footprint. It cut a decent 350 kilograms CO2e from the Molloy diet, but only if they stuck to plant-based fasting food with a little fish, egg or chicken. A 'fasting' dinner of steak blew the budget.

I tested out vegetarianism. I loved the creamy, cheesy pasta but I ate too much and my seafood choices weren't environmentally sustainable. Besides, I only cut 66 kilograms of CO2e from my annual footprint. The Molloys did better because their baseline diet has so much meat. They'd save 450 kilograms CO2e, but if we all eat fish like that the oceans will run out.

I looked at an environmental ogre, food packaging, and found it wasn't that bad. Embedded emissions in my packaging, including the plastic, only accounted for 3% of my food's total footprint. If I'd tried to reduce it by shopping at a co-op or market instead of my local supermarket, the long drive would have emitted more carbon than I'd save. Worse, the packaging preserves the food, serves it in small portions and increases shelf life. These all cut down on food waste. Stripping the plastic off meat, fish and cheese, in particular, will drastically increase emissions because some of that product will end up in the bin.

I examined another eco-favourite, eating local, seasonal and organic. I found no evidence that this would cut emissions and in some cases, eating local or seasonal will increase emissions. Organic food probably cuts carbon, but not by much. If you have to drive out of your way to a specialty shop to buy it, the drive probably cancels out any savings.

A rainbow of fruit and vegetables

What worked?

A vegan diet was the clear winner. It would cut my food footprint by over half and cut the Molloys' by two-thirds. But I'm not sure I'm a good enough person to sustain it. I can't imagine shunning Grandma's roast chicken. But decreasing meat and dairy and taking on a few more vegan options are easy and delicious steps anyone can manage.

I also saved a hundred kilograms of CO2e by cutting food waste for myself and the Molloys. I didn't worry about packaging. Instead, I focussed on the food that gets lost through our industrial system. A few simple steps made a big difference.

For this week's experiment, I bundled all this information together to make a long-term plan to cut CO2e for myself and the average Australian. I focussed on supermarket swaps and easy steps that anyone could take.

Simple Swaps

My Friday night takeaway binge and weekend steak blew my budget. I hadn't realised that beef generates over five times the emissions of chicken, kangaroo, pork and duck. We'll still eat meat every Saturday night, but we'll only have beef or lamb once a month. We also eat a lot of eggs, but our backyard chooks cut down on the CO2e. I'll choose a low-meat Friday takeaway with little chicken or cheese and I'll go vegan for many other meals. I've also cut my food waste. All up, this takes my food footprint from almost 1.4 tonnes CO2e to 850 kilograms CO2e.

The average Australian can cut even more because they start out eating more meat, fish and dairy. I went through the Molloy weekly shop and made some swaps. I changed beef for beans, chicken for tofu, endangered orange roughy for a sustainable and low-carbon mackerel, pork for mock meat and cream for yogurt or cashew butter. I put in salmon, hummus and pesto for sandwiches instead of ham and massive amounts of unsustainable tinned tuna. I swapped 1.7 litres of cow milk for non-dairy milk but I left in 600mL cow milk and all their cheese, eggs, yogurt and butter. This gave them a varied diet with plenty of dairy, 320g of meat (kangaroo, duck, chicken and monthly lamb) and 500g fish per person per week. I also assumed they'd follow some simple steps to reduce food waste, no dumpster diving required.

All up, this would take the average Australian Molloy diet from a whopping 1.9 tonnes to 1.16 tonnes CO2e per person per year. The adults could save even more by going vegan, going vegetarian or doing 5:2 fasting, provided they ate no red meat on their fasting days.

Meat choices matter

Some fruits and vegetables have a higher carbon factor than others but they're all fairly low. If you're vegan, I think you eat whatever you like. That's not the case for meat and seafood.

I've heard various meat industry lines over the years, including that meat is nutritionally essential, that it's so nutritionally dense it gives good environmental value and that Australian beef and lamb are environmentally friendly choices because they're lower carbon than international ruminants. None of these claims stacks up against the data.

Fish is also complex. Much of it is less carbon intense than meat (with a few exceptions, like prawns and lobster). But even low-carbon choices may not be sustainable. The fishing industry is poorly regulated, overfishes and uses massively destruction techniques like trawling. Many commonly-eaten species are likely to be extinct in the next decade. I recommend eating less and checking with the Australian Seafood Guide before buying fish or seafood.

Chart shows that beef and lamb generate more carbon than chicken, salmon and duck

Australian beef generates fewer emissions than overseas beef, but it's still seven times more intense than duck.

What didn't I cover?

I'd love to spend a year looking at food, but then I wouldn't cover the rest of my carbon footprint. I've had to skip some interesting topics. I think eating offal instead of muscle meat and eating backyard produce cut a lot of carbon, but I didn't run the numbers to check. I have no idea how home-prepared food stacks up against food bought out in restaurants, cafes and fast food joints. I didn't look at freezing and refrigeration in transit. I factored in food processing, but I think I over-compensated. I also suspect that home-delivered food from a supermarket in major metro areas saves carbon because the trucks and delivery routes are more efficient than your car, but I haven't run the numbers to see.

I tried to look at hothouses and greenhouses. Fruit and vegetables that are grown in greenhouses usually have a bigger carbon footprint, but not always. For food miles, I found that while sea freight and road transport don't have a big impact, aeroplane miles do. Unfortunately, I couldn't use the data I found because neither supermarket websites nor food labels showed air freight or greenhouse technology. I've written to the three major supermarkets about this and I hope to cover it in my book next year.

I also left out drinks (other than milk). For most people, that means bottled water and soft drinks. For me, it's booze. I'll circle back to this topic when I make my annual New Year's resolution to drink less. Until then, happy holidays to you and your family!

broken image

Bizarro Comic by Dan Piraro.