The Negative Carbon Diet To The Rescue?

For a while now I have been digesting the idea of a negative carbon diet and whether it is even possible and recently I’ve come across my answer.

But before I reveal all, let me give you some background. I base the name of my “diet” on the negative calorie diet which involves eating foods that contain fewer calories than your body uses in the process of digesting them – in effect they take energy to eat.

My spin on this is the negative carbon diet which basically means that the carbon footprint of the food you are eating is less in terms of grams of CO₂ equivalent than the weight of the food itself. Disclaimer: it has nothing to do with losing weight!

Ok so it’s not technically a negative carbon diet – the emissions still occur but they are super low in comparison to the typical meal.

It All Started At The Breakfast Table

I first thought about my food’s carbon footprint when I came across Tesco’s carbon labelling for milk (800g per pint of semi-skimmed) and since then I have switched completely away from cow’s milk to one of the alternatives.

But the idea that the carbon footprint of the milk was more than the weight of the milk itself never really left me and I have often wondered whether you can eat an entire diet where emissions are less than the weight of the food.

Enter the negative carbon diet.

I own, and regularly refer to, a book by Mike Berners-Lee called How Bad Are Bananas? (highly recommended) which sheds light on the carbon footprints of various foods but I’ve just come across what I suspect is the complete list of products of which Tesco have calculated the carbon footprints.

Based on this list, I have concluded that the negative carbon diet is not really possible unless you eat a fruitarian diet which is wholly unrealistic.

But I do think you can have negative carbon meals even if it isn’t easy.

My breakfast this morning was negative carbon because I had a bowl of Bran Flakes (80g CO₂e per 30g serving) served with Oatly oat drink (one of my chosen cow’s milk alternatives with a carbon footprint of 250g per litre). Not very exciting I know but a nutritious AND environmentally friendly start to the day.

Lunch and dinner start to get a bit trickier because looking at the list provided by Tesco, I can only see these ‘negative carbon’ foods:

• carrots (not those found in a tin though)
• some types of potato
• passata (puréed ripe tomatoes)

That is a very small list! I suspect there are some more hiding in there though such as the dried pasta which soaks up a lot of water during cooking which makes the figure of 220gCO₂e per 75g serving for their quick cook penne a little misleading for example.

I was actually surprised by some of the footprints that have been calculated with mushrooms being of particular note. I’d have thought they would have a tiny carbon footprint because of how they are grow and harvested but clearly I am wrong because they start at 460gCO₂e per 100g serving.

A Recipe For Disaster?

So tonight, in the spirit of the negative carbon diet, I’m going to have:

• wholewheat spaghetti (240gCO₂e per 75g serving but ok using logic above)
• passata (80gCO₂e per 100g serving)
• white potatoes (220gCO₂e per 250g serving)
• extra virgin olive oil (71gCO₂e per 15g serving)
• garlic, thyme and seasoning to add some flavour

Basically, I’ve mixed a coupled of recipes I found online together and it’ll probably be as simple as:

1. peel and cut potatoes into small cubes
2. place potatoes onto a sparingly oiled, pre heated baking tray and drizzle with a little more oil, sprinkle thyme, salt and add a generous amount of garlic (I already have a jar of finely chopped garlic in my fridge but you could use whole cloves if you wish).
3. cook until crispy (I’m guessing about 25 minutes at 220c in my oven)
4. add spaghetti to a pan of boiling water for 10-12 minutes, stirring occasionally
5. drain spaghetti and add passata and cook for a further 90 seconds
6. serve the lot and enjoy

I suppose I could add some carrots but I probably won’t on this first experimental venture.

Be warned – I am not a particularly good cook and the times and temperatures above are complete guess work so you’ll probably know better than me.

Be warned (again) – this recipe is one that old Dr Atkins would freak out at because it is seriously carbolicious – just thought I’d warn you if you care about things like that.

The result:

I’d say it turned out as good as I could have expected. I was a bit concerned that this meal would have been a bit boring but it was actually pretty nice with the garlic potatoes working well with the passata. I’d definitely have something like this again.

How Much Attention Should We Pay To Food Then?

Seeing as it is incredibly difficult to eat a diet where the carbon footprint is less than the weight of the food, should we all just forget it and eat what we like?

Well yes and no. I certainly wouldn’t attempt to eat my negative carbon diet every day but I won’t be going out and gorging myself on meat, cheese (and mushrooms!) either.

There’s little doubt that going veggie (like I did for a week) is generally better for the planet than eating meat but even then there are some surprises such as the mushrooms so it’s not always straightforward to make a low carbon meal.

Alas, I think my negative carbon approach is a little unrealistic in the long term but at least now I know.

How much do you consider the environmental impact of what you are eating each day? Let me know by leaving a comment below.

Steve (132 Posts)

Chief writer and editor on Green Steve. Blogging since 2011, Steve likes to delve into a wide number of topics.