- Solution 1: Cutting back on meat
- Solution 2: Beans for Beef
- Case Study: Fish
- Solution 3: Mollusks
- Solution 4: Edible Insects
Please note: “meat” on this page refers to domestic livestock and fish. It does not include hunted or trapped game, and other country foods.
In general, domestic meat has a larger carbon footprint than plant protein sources. Livestock requires land to be designated for their feed. For example, to produce 1 kg of beef requires 5 – 7 kg of grain. This grain could otherwise be designated for human consumption or left as forested land.
In comparison, plant protein, such as legumes, can be immediately processed for human consumption.
Livestock production accounts for 70% of global agricultural land use. Due to growing agricultural demand, deforestation is a major concern, especially as trees are essential in removing carbon dioxide. Additionally, livestock contribute 18% of global GHGs, mainly in the form of methane and nitrous oxide.
It is important to note that livestock play an important role in an agricultural ecosystem. Livestock help keep a natural balance of fertilizing the land and even sequestering carbon. However, like everything, the key is to moderate the amount of meat consumed.
There are many different diets that aim to reduce meat consumption. No one diet can be considered the be all end all. Both meat-based and plant-based diets produce significant amounts of GHGs, use substantial amounts of water, and require large areas of low carbon sequestering land (4).
The following chart shows some data collected from real people that self-selected their diets. While it provides a great idea of the approximate amount of GHGs that are generated, these numbers would certainly change from person to person. As well, these numbers do not include food waste. Studies have found that fruit and vegetables make up a higher proportion of food waste than meat.
Diet | kgCO2e per day | kgCO2e per year |
High meat eaters (>100g per day) | 7.2 | 2,624 |
Medium meat eaters (50-99g per day) | 5.6 | 2,055 |
Low meat eaters (<50g per day) | 4.7 | 1,705 |
Fish eaters | 3.9 | 1,424 |
Vegetarians | 3.8 | 1,387 |
Vegans | 2.9 | 1,059 |
Data source: Environmental Working Group (EWG)’s 2011 Meat Eater’s Guide, found here.
Solution 1: Cutting back on meat
Cutting back on meat once or twice per week makes a big difference.
Switching from a high to low meat diet would result in a reduction of almost 1 tonne of GHG emissions (919.8 kgCO2e per person per year)! (A family running a 10 year old small family car for 9,560 km has a carbon footprint of 2,440 kgCO2e.)
The following chart provides insight into the carbon and water intensity of different protein sources.
Protein Source | kgCO2e per pound | Car km equivalent | Water footprint (litre per kg) |
Lamb | 39.2 | 146 | 10,400 |
Beef | 27.0 | 101 | 15,400 |
Pork | 12.1 | 45 | 6,000 |
Farmed Salmon | 11.9 | 44 | NA |
Turkey | 10.9 | 40 | NA |
Chicken | 6.9 | 26 | 4,325 |
Canned Tuna | 6.1 | 23 | NA |
Eggs | 4.8 | 18 | NA |
Peanut Butter | 2.5 | 9 | NA |
Dry Beans & Tofu | 2.0 | 7 | NA |
Lentils | 0.9 | 3 | NA |
Data Source: Green Eatz
Source: Environmental Working Group (EWG)’s 2011 Meat Eater’s Guide, found here.
Solution 2: Beans for Beef
Methane is a major greenhouse gas that is emitted from livestock, particularly cows. Beef production alone is responsible for 37% of the human-related methane released. Plus, methane is 25 times more powerful than carbon dioxide.
If cutting out all meat is unrealistic, reducing beef consumption can make a huge impact. As seen in the above chart, beef generates 27 kgCO2e per pound, whereas dry beans only creates 2 kgCO2e per pound.
The following chart provides the nutritional benefits between these two protein sources to demonstrate that the additional inputs that go into livestock do not translate into additional nutrition for human consumption.
5-ounce steak | 1 cup (5 ounces) pinto beans | |
Calories | 300 | 265 |
Protein (g) | 44 | 15 |
Cholesterol (mg) | 120 | 0 |
Fat (g) | 12 (saturated) | 1 (polyunsaturated) |
Complex Carbohydrates | 0 | 26 |
Dietary Fibre | 0 | 15 |
Potassium | Less | More |
Sodium | More | Less |
Iron | Equal | Equal |
Price | High | Low |
Nutritional Differences: 5 ounce steak vs. 1 cup (5 ounces) of pinto beans, data sourced from here.
Case Study: Fish
While fish may have a lower carbon footprint than ruminants, there are serious concerns with the sustainability of the fishing industry.
Approximately 90% of global fish stocks are either fully fished or overfished (read more here). Many fishing and farming methods result in habitat damage and by-catch – in which unintended fish species are picked up and not used. The result is serious ecosystem damage. Unsustainable fishing methods are making it more difficult to support the growing demand for fish as a protein source.
Human-driven climate change is also impacting the availability of fish species. Without proper GHG reductions and improved fishing management, there may become an even greater demand for protein sources that are more carbon-intensive than fish.
Solution: If choosing fish, follow the Ocean Wise seafood recommendations chart, found here. It is a comprehensive guide to “sustainable” and “not-recommended” species. Alternatively, buy or fish local Manitoban species.
Solution 3: Mollusks
Aquaculture has many possibilities to meet the demand of a growing population, yet more sustainable measures are needed. Currently 99% of the Atlantic salmon on the market is farmed. While there are arguments to be made in favour of aquaculture, farming carnivorous fish requires that their wild prey species need to be exploited just to feed them.
In fact, approximately 27% of the annual global catch is used just to feed farmed fish. As seen with other meats, such as beef, the additional inputs for the animals do not translate into more protein for us. Therefore, researchers are suggesting a transition to mollusks; choosing oysters, mussels, and clams, rather than fish, shrimp, and octopus.
While there are still some ecological concerns associated with bivalves – such as their ability to quickly become invasive (ex. the zebra mussel) – these food sources are lower on the food chain so require little feed (5).
Solution 4: Edible Insects
The future of animal-based protein has hit the shelves in many large grocery stores across Canada: edible insects!
While it may require some psychological adjustments, edible insects- including crickets and mealworms – are an excellent source of proteins, fats, vitamins, and minerals.
Plus, they have a great food efficiency conversion (amount of inputs required compared to nutritional benefits gained by consumers), have low amounts of GHG emissions associated with their production, and require very little water and land resources. Eating insects also provides a wider range of options for different countries around the world, compared to the idea that every country needs chicken, beef, pork, and other popular meats. This “new” protein source is also being praised as being an efficient solution for feeding low-income communities (6).