Over recent years I’ve grown steadily more aware of agriculture’s negative impact on the planet. It’s now understood that food production is responsible for around ⅓ of worldwide greenhouse gas (GHG) emissions (1). I wanted to find out how I could help reduce this footprint. After researching different diets and foods I came to realise how and what you eat can have a big impact on reducing carbon emissions. Over the past few months I’ve been reading lots of research papers, obsessing over the emissions of different foods. Now I think I’ve got a pretty great picture about what constitutes a “low carbon” meal. In this article I’ll share what I’ve learned and give you four simple tips to reduce the footprint of your dinner plate.

Eat Less Meat And Dairy

The first thing that you can do to reduce your food emissions is eat less meat or even cut it out entirely. Indeed, livestock is one of the biggest contributors to the agricultural carbon footprint (2,3,4). Why? Simply put, meat production is incredibly inefficient. It takes a vast amount of energy and resources to rear, slaughter, and prepare an animal to be eaten. To illustrate how inefficient meat is, take the following example: producing 100g of beef protein produces around 50 kg of GHG emissions. That’s on average as polluting as producing 12,500g of pea protein (5).

Dairy is a high-carbon food for the same reasons as meat; it’s inefficient to rear and farm the livestock that produces it. Making 100g of cheese protein produces around 11 kg of GHG emissions. This is around 5x worse than a tofu based equivalent or 13x worse than an equivalent made from pulses (6). But, what might surprise you is cheese has worse GHG footprint than chicken, pork and farmed fish (7). So many would do well to treat cheese as an equivalent to meat.

Studies show that if you cut out meat and dairy entirely you could save 35–49% GHG from your diet (8,9,10). So, if you want to be as environmental as possible, you might want to think about going vegan. However, this might be a bit extreme for the majority of people. If you’re not looking to cut out meat and dairy entirely, a balanced approach to your diet can still cut out a big chunk of GHG emissions.

For example, limiting meat and dairy consumption to a few meals throughout the week can help you reduce your carbon footprint. Try by having the majority of your meals plant-based, saving meat and dairy to around 2–3 nights a week. By dialling back your meat consumption in this manner you could save around 21% GHG from your diet (11).

It is also beneficial to switch to less carbon-intensive meats. Beef and lamb are routinely cited as the most polluting meats, so try to go for chicken, pork and fish instead. Switching your meat consumption to less polluting livestock can save an average of 20% GHG emissions from your diet (12). Going pescatarian can give you another 7% saving with a 27% GHG reduction in your diet (13). If you’re out at a restaurant and decide to eat meat but are struggling to remember what’s the greenest option, as a general rule of thumb, lighter meats are less polluting.

By curtailing the amount of meat and dairy you have during the week you can significantly reduce the carbon footprint of your eating. A majority or solely plant based diet is great way to eat the planet green. But there are other factors that you will need to watch out for if you want to further limit your emissions. We’ll cover those next.

Avoid Air-Freight At All Cost

Importing food from overseas is not as bad as many may believe. Transport represents a very small portion of the overall GHG impact for most foods (14). That being said, the number of “food miles” added after product leaves the farm gate does incrementally add C02. So it’s best to try and eat as locally as you can. But this is not always preferable, see the next section to find out more.

What is more important than distance traveled is the method of transport. Below is a table representing the common forms of food transport and their corresponding C02 impact.

(15)

Air freight is by far and beyond the worst offender. Shipping foods by air adds a considerable footprint to the end product, and in turn to your dinner plate. For example, in the UK, if you eat a 250g packet of local Asparagus in-season this represents a carbon footprint of around 125g of GHG. But if you were to eat that same packet air-shipped from Chile it would have a footprint of 3.5kg of GHG (16). Thus the air-freighted asparagus is almost 2x worse in terms of GHG impact than eating the equivalent amount of British lamb (17)!

The problem with air-freight is that most suppliers/supermarkets don’t mark the method of transport used when selling produce. So how can you avoid food that has been air-freighted? I came up with a handy acronym — OLOS, which can help you make a good estimate:

Out of season locally or Labelled as coming from Overseas and has a Short shelf life = air freight

Good examples of short shelf life foods are: strawberries, sugar-snap peas, tomatoes and lettuce. In general if you stick to the above rule you can avoid the majority of air-freighted goods. However, one way to avoid them all together is to eat seasonally — let’s talk about this a bit more in the next section.

Eat Seasonally

It was only relatively recently that the we got used to having a huge range of foods available all year round. The rise of global trade has ushered in unfettered food abundance for wealthier nations. This has been positive in many cases, but has made us forget the bond between our local agricultural calendar and our palate.

By eating in season food you’re going to get the tastiest of the produce but also the most environmentally friendly. Seasonal produce is much more local meaning you won’t have to worry too much about “food miles” or air-freight (see the previous section). But more importantly, it means that you will also avoid produce that has been grown out-of-season in artificially re-created conditions.

Farmers, under pressure of imported out-of-season goods during the winter, produce “summer” vegetables in heated greenhouses. This uses considerably more energy than traditional production. Innocent looking vegetables produced in this manner have some of the worst environmental credentials around.

Take British organic tomatoes as an example. Produced in the summer growing months, organic tomatoes have a very favourable impact of 400g GHG per kg — about a 1/10th of the emissions it takes to produce the equivalent weight of a British chicken (18). In contrast, buying organic on-the-vine cherry tomatoes in March means they are produced in heated glasshouses — and their carbon footprint rises to a whopping 50kg GHG per kg (19). This is over two times more GHG per kilogram than British beef, traditionally seen as the most polluting meat (20).

If you eat in season you’ll sidestep this problem. Gravitating towards food naturally produced in your local climate. Produce which has been grown with minimal additional energy. It’s also incredibly rewarding and fun to eat with the seasons. There are some great resources out there to find out what’s in season when. In the UK there’s the excellent eat the seasons which has a North American counterpart. BBC also has a handy table which is less accurate but more user friendly.

Plan Your Meals

Around 30–50% of all food produced is wasted before it can be a bought (21). But even more worryingly around 19% purchased food is also wasted (22). This figure represents the amount food that, after purchase, is spoiled or thrown away. Avoiding food waste is important because it causes the farming system to produce an excess of what is actually needed. Obviously more food production means more emissions are generated.

You might think that binning a few mouldy carrots here and there won’t have much impact. But that’s actually wrong: it’s estimated that cutting out all avoidable waste from your diet can give you GHG savings of around 12% of your total diet emissions (23). In other words if you were to waste as little as possible for just a week you would save the same amount of GHG that it takes to drive 61km in an average car produced in 2018 (24). Not bad!

The easiest and simplest way for you to cut down on your food waste is to plan your week’s food. Most food is spoiled because it’s left in the cupboard or fridge for too long and goes off. Proper meal planning will help you shop correctly and spread ingredients throughout the week. I recommend sitting down on a Sunday and plan out the weeks meals ahead. Be sure to always check what you have already in the fridge or other perishables when doing this.

Conclusion (TLDR)

In summary if you are looking to eat as low-carbon as possible you should:

Cut back or cut out meat and dairy from your diet. If you’re not cutting out meat entirely try shifting to less carbon-intensive meats. These include (broadly in order from best to worst): fish, chicken, pork.

Try and eat locally, especially avoiding food that has been air freighted. Use the OLOS method to work out if a food has been air shipped.

method to work out if a food has been air shipped. Eat seasonally. Adapt your palate and recipes throughout the year. Above all steer clear of out-of-season food that has been produced locally; most likely it has been produced in a heated greenhouse. Buying food produced in a heated greenhouse is environmentally worse than importing.

Reduce your food wastage by planning your weekly meals. Cycle your cupboards and fridge to use leftover produce.

And if you are looking for inspiration check out my site lowly. I research and publish low carbon recipes weekly. Each recipe has a carbon footprint breakdown by ingredient and total emissions saved by eating the meal. Stop by and say hi!