Climate-friendly food

Key actions in climate change mitigation include using less animal-based foods while eating more vegetables, cutting down food waste, choosing in some cases organically and locally produced food, improving energy efficiency in food production, preparation and storage, and rationalising shopping trips.

With moderation and vegetables

With regard to the impact of consumption on climate change, food contributes almost as much as transport or housing. Consequently, favouring climate-friendly food is an important factor in climate change mitigation [1]. Simple measures can make a diet more climate-friendly, and often a climate-friendly diet is also healthy [2] because it contains plenty of vegetables. It may also include some domestic meat, since balanced agriculture requires also livestock production.

The plate model remains a useful tool in meal planning because it ensures a balanced diet. Opting for vegetarian meals one or two days a week is a good way of reducing the burden on climate. The simplest way of moving towards a vegetarian diet is to replace meat in familiar dishes with protein from vegetable sources. Choose seasonal vegetables: mainly root vegetables and berries in winter and fresh seasonal produce, such as salad and tomatoes, in summer.

Avoiding empty calories benefits climate, waistline and wallet

Foods with poor nutritional value, such as sweets, soft drinks, alcohol and crisps, contribute to climate emissions [3]. Using less of them reduces the climate burden and helps weight loss. It may also save money because such foods can account for up to 40% of the food bill [4].

Many good reasons to eat less meat

Broiler meat, followed by pork, produce the least amount of climate emissions. The impact of beef on climate represents 15kg of carbon dioxide emissions (per a kilogram of meat as CO2 equivalent) whereas the impact of pork and broiler are respectively 5kg CO2/kg of meat and 4kg CO2/kg of meat (Table 1). The impact of cheese is nearly as high as beef (13kg CO2/kg of meat). Conversely, climate emissions of soy account for about 1kg CO2/kg of soybeans. The climate diet calculator [5] can be used to estimate how much consumption and diet contribute to climate change and compare the effects of different vegetable- and meat-based diets on climate.

Table 1. Estimated contribution of different foods to climate change[5].

Food

Impact of climate kg CO2 equivalent/kg

Beef

15

Cheese

13

Pork

5

Broiler

4

Tomato, cucumber (greenhouse in winter)

5

Rice

5

Vegetable oil

3

Eggs

2,5

Fish

1,5

Rye bread

1,3

Sugar

1,1

Dried beans

0,7

Berries, vegetables, potatoes

0,2

Globally animal production not only causes significant greenhouse gas emissions but also diminishes areas previously reserved for natural habitat or other food production. The areas currently in cultivation would provide enough produce to feed the world's population. However, as meat consumption is on the increase, more forests are being converted to fields. Meat production requires more arable land than the production of vegetable-based foods. For example, about 10kg of plant-based feed is required to produce 1kg of meat [6]. A little over 25% of the world's landmass is currently used either for grazing or growing forage crops [7].

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Reducing meat portions and choosing vegetable proteins

In recent times, the size of meat portions has grown significantly. In 2007, a Finn living on a mixed diet consumed 79kg of meat per year, or 200g per day. The recommended portion sizes for meat are often exceeded. The protein requirement can be met with vegetable sources of protein while the amount of meat is significantly reduced. In order to keep agricultural emissions under control, meat consumption per person should not exceed 90g of meat per day or 33kg per year. The proportion of ruminant meat should not exceed 50g per day [?] . Vegetable sources of protein alone can meet the need for protein. Smaller portion sizes would lower both food costs and the carbon footprint – and solve many health problems. For example, cutting down meat consumption reduces the risk of heart conditions, obesity, bowel cancer and possibly some other cancers [?] .

Meat can be swapped for many protein-rich vegetables, such as:

  • soybean
  • broad bean
  • other beans, lentils and peas
  • nuts and seeds, particularly oilseed hemp seeds
  • wholemeal grains and wheatgerm
  • sweet cultivars of lupin
  • seitan (wheat gluten)

About agricultural climate emissions

The major greenhouse gases emitted in the food production chain are carbon dioxide, methane and nitrous oxide. Manure and the digestive process in livestock (accounting for some third of emissions created by humans) and rice paddy fields are sources of methane, a strong greenhouse gas. [?] Nitrous oxide is released, among other sources, by the use of nitrogen fertilisers and indirectly by conversion of rainforests to new areas of cultivation and pasture. Production of nitrogen fertilisers is also very energy-intensive.

Estimates of the global greenhouse gas emissions from agriculture (measured by carbon dioxide equivalents) out of all greenhouse gas emissions caused by humans vary between 10% and 18% [?] [?] , some state that the share could be 50% of global greenhouse gas emissions [8]. The magnitude of the estimates depends on what emission sources are included in the calculations. For example the calculations of FAO include among other things indirect emissions from land use changes, e.g. converting forests to fields [?] . In Finland, the estimates vary between 7% and 18% [?] .

Greenhouse cultivation in winter

In the northern countries, producing greenhouse vegetables in winter is a significant source of greenhouse gas emissions. The carbon footprint of tomatoes grown in Finland in winter is 5–7kg per a kilogram of tomatoes, whereas the carbon footprint of tomatoes imported from Spain is only about 0.5kg per a kilogram of tomatoes [9]. Nevertheless, Spanish tomatoes may not make a good alternative because of the large amounts of water and pesticides used in their cultivation. Figure 1 shows how different varieties of salad affect climate change. Consequently, the best salads are made of Finnish vegetables grown outdoors.

Impact of different salads on climate change

Figure 1. Impact of different salads on climate change (CO2 equivalent) [10]

Organic food often has less environmental impact than conventionally grown food

It has been estimated that organic farming could reduce greenhouse gas emissions amoung other things by increasing the amount of soil organic carbon (humus) [11]. Humus improves the ability of soil to retain water and nutrients. According to some studies, organic animal production can cause higher climate emissions than conventional farming due to organically-reared animals having a slower growth rate and smaller production values per animal [12]. Research by the Finnish Environment Institute [13] shows that, with regard to the total environmental impact, organic milk production is a better alternative to conventional production, while emissions from the organic cultivation of rye do not always differ from those of conventional methods. Research has shown that the best solution for the environment is to combine milk production with crop cultivation in order to achieve efficient recycling of nutrients.

Transport and shopping trips add to emissions in the food production chain

In transport, factors that mostly add to the greenhouse gas emissions are the mode of transport (ship, truck or airplane) and the type of food (fresh, frozen etc.). In the entire production chain, long-distance shipping usually accounts only for a small share of the total carbon dioxide emissions [14]. This is explained by the large shipping quantities. When emissions are spread between the transported goods, emissions for a single product remain low. Goods transported by air or road clearly have a greater impact on climate change than those transported by sea. Consumer shopping trips can add considerably to the lifecycle emissions of a product. For the environment, the worst kind of shopping trip is the one where a single item is collected by car. Shoppers should opt for walking, cycling or taking the bus. When using a car, it is better to collect a large quantity of food during a single trip.

Is it good to support local food production?

Recently, the opinion that local produce might not be as good for the climate as was previously thought has been a subject of much debate. This opinion is true for winter greenhouse tomatoes and cucumbers but, in the main, the environmental impact of local produce should be measured case by case. As a rule of thumb, domestic vegetables and meat often provide a better option than imported ones, and a vegetable source of protein, even an imported one, is better than meat. For example, using soy as a source of protein is more climate-friendly than using meat because soy has a lower environmental load (such as eutrophication and impact on climate). However, locally produced organic meat may in some cases have a lower environmental load than vegetarian food due factors such as airfreight, certain cultivation methods or the use of frozen produce. If vegetarian diet contains many exotic foodstuffs, it may also have more adverse effects on climate than meat [15]. Even though transport accounts only for a small share of the total food production emissions, buying local produce is usually recommendable because it also helps maintain local economies, food security and the vitality of rural areas. Buying local produce means that the environmental impact will be felt in the immediate surroundings rather than the environmental burden of cultivation being foisted on other countries[10].

Food should not go to waste

Finns throw away 70kg of food every year. About 10% of food bought in Finland is goes to waste [16]. If food waste if not recycled, it can cause high levels of methane emissions in landfill sites. Climate-friendly eating also means buying only what you need and finishing your meals. Edible food should not be thrown away. A Swedish study suggests that the environmental footprint of wasted food is almost as big as that of beef. In Sweden, greenhouse gas emissions would be cut down 5% if pork or chicken were used instead of beef or if people stopped wasting food and overeating [3].

Preparing and storing food

Energy consumption is an important factor in food preparation, accounting for 6% of the household electricity bill [?] . As the oven is the most energy-intensive appliance, it makes sense to prepare a large amount of food when using it. Preparing food in the microwave is eco-efficient. Making porridge in the microwave rather than on the cooker reduces the impact on the climate by some 70% (Figure 2). As the storage and transport of frozen semi-prepared foods are very energy-intensive, it is better to avoid them. See the tips for eco-efficient cooking published by the Martha Organisation.

CO2 emissions of porridge

Figure 2. CO2 emissions of the production of oatmeal and the making of porridge per 10,000 packages of 1kg consumed. Greenhouse gas emissions from making porridge according to portion size and cooking method [17]

Food storage accounts for 13% of the household electricity bill [?] . Energy-efficient refrigeration is possible: the factors to keep in mind include the correct placement of appliances, maintaining correct temperatures and defrosting the freezer regularly [18]. When buying new appliances, the energy rating is important, and there are also many other sources of information available for making energy-efficient choices [19]. Retailers can do their share for lowering greenhouse gas emissions in the food production chain by reducing the energy consumption of their refrigerators and stocking less produce that requires cold storage.

Checklist for climate-friendly eating

  • Use more plant-based products and eat less meat and other animal-based products.
  • Go vegetarian for at least one day a week.
  • Do not throw away food!
  • Prefer vegetables that have been grown outdoors and shun vegetables grown in greenhouses in winter or transported for long distances.
  • Choose potatoes and a variety of grains, such as barley, but avoid rice.
  • Prefer organic.
  • Choose wild fish, seasonal berries and mushrooms.
  • Choose seasonal vegetables but wait until their season has genuinely begun.
  • Avoid frozen produce.
  • Prefer products with the least packaging and buy large package sizes.
  • Finish your meals and do not buy more food than you need.
  • When cooking, prepare extra portions for heating up in the microwave.
  • Plan your shopping trips and walk, cycle or use public transport. When driving, buy enough food in one trip.
  • Recycle food waste.

References

  1. Seppälä et al. 2009. Suomen kansantalouden materiaalivirtojen ympäristövaikutusten arviointi ENVIMAT-mallilla. Suomen ympäristö 20/2009. Envimat-hanke. http://www.ymparisto.fi/default.asp?contentid=334235&lan=fi&clan=fi
  2. Terveellinen ruoka voi olla myös ekologista. Helsingin sanomat. Vieraskynä 1.5.2010 Mikael Fogelholm. http://www.hs.fi/paakirjoitus/artikkeli/Terveellinen+ruoka+voi+olla+my%C3%B6s+ekologista/1135256513891
  3. Jordbruksverket. 2009. Hållbar konsumtion av jordbruksvaror – hur påverkas klimat och miljö av olika matvanor? (pdf) Rapport 2009:20. http://www.jordbruksverket.se/download/18.72e5f95412548d58c2c80002944/ra...
  4. Ruotsalaiskuluttaja ei maksa ekstraa kestävistä ruokavalinnoista. Ruokatieto 8.4.2009. Uutiset > 2009 > Arkistoitu uutinen. http://uutiset.ruokatieto.fi/WebRoot/1043198/X_Arkistoitu_uutinen_tai_tiedote.aspx?id=1094002&NewsItem=2853 [viitattu 30.11.2010]
  5. Nissinen, A. Salo, M. ja Grönroos, J. 2010. Ilmastodieettipuntari – mihin sen antamat ilmastopainot perustuvat? (pdf) Versio 23.4.2010. http://ilmastodieetti.fi/Ilmastodieettilaskurin-perusteet_2010-04-23.pdf
  6. Reijnders, L. and Soret, S. 2003. Quantification of the environmental impact of different dietary protein choices. American Journal of Clinical Nutrition, Vol. 78, No. 3, 664S-668S. http://www.ajcn.org/cgi/content/full/78/3/664S
  7. Steinfeld et al. 2006. (FAO) Livestock’s long shadow. Environmental issues and options. Tutkimus pdf-tiedostona. ftp://ftp.fao.org/docrep/fao/010/a0701e/a0701e00.pdf
  8. Goodland, R. & Anhang, J. 2009. Livestock and Climate Change. Worldwatch Institute. http://www.worldwatch.org/files/pdf/Livestock%20and%20Climate%20Change.pdf
  9. Kotimaisen tomaatin syntinä hiilijalanjälki. Helsingin sanomat. Julkaistu 19.4.2009. http://m.hs.fi/inf/infomo?site=hstxt&view=news_talous_child&feed:a=hs.fi&feed:c=news&feed:i=1135245278529
  10. MTT luonnonvarapuntari. Koottua tietoa luonnonvarojen kestävästä käytöstä. https://portal.mtt.fi/portal/page/portal/Luonnonvarapuntari/Ymp%E4rist%F61/Ruoan%20ymp%E4rist%F6vaikutukset [viitattu 3.5.2010]
  11. Azeez, G. 2009.Soil carbon and organic farming. A review of the evidence of agriculture´s potential to combat climate change. Summary of findings. Soil Association, Bristol. 15 p. http://www.soilassociation.org/LinkClick.aspx?fileticket=BVTfaXnaQYc%3D&
  12. Garnett, T. 2008. Cooking up a storm. Food, greenhouse gas emissions and our changing climate(pdf). Food Climate Research Network. Centre for Environmental Strategy, University of Surrey. http://www.fcrn.org.uk/sites/default/files/CuaS_web.pdf
  13. Grönroos, J. & Seppälä J. (toim.). 2000. Maatalouden tuotantotavat ja ympäristö. Suomen ympäristö 431. Luonto ja luonnonvarat. 244 s. http://www.ymparisto.fi/default.asp?contentid=84103&lan=fi
  14. Weber, C. L., and Matthews, H. S. 2008. Food-Miles and the Relative Climate Impacts of Food Choices in the United States (pdf). Environ. Sci. Technol., 2008, 42 (10), pp 3508–3513. http://psufoodscience.typepad.com/psu_food_science/files/es702969f.pdf
  15. Carlsson-Kanyama, A. 1998. Climate change and dietary choices - how can emissions of greenhouse gases from food consumption be reduced? Food Policy, vol 23, no.3/4.
  16. Katajajuuri, J.-M. ja Vinnari, M. 2008. Jokapäiväinen leipämme. Kaikesta jää jälki – puheenvuoroja ympäristöä säästävistä valinnoista. Avain 2008.
  17. Katajajuuri, J.-M., Virtanen, Y., Voutilainen, P., Tuhkanen, H.-R. & Kurppa, S. 2003. Elintarvikkeiden ympäristövaikutukset: FOODCHAIN (pdf). MMM:n julkaisuja 2003:6, 64 p. http://wwwb.mmm.fi/julkaisut/julkaisusarja/MMMjulkaisu2003_6.pdf
  18. Motiva.10.11.2010.Näin säästät energiaa keittiössä. http://www.motiva.fi/koti_ja_asuminen/nain_saastat_energiaa/sahko/keittio [viitattu 30.11.2010]
  19. Motiva. 14.10.2010. Ostajan opas. http://www.motiva.fi/koti_ja_asuminen/ostajan_opas

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