Most teenagers tend to adopt the same diet as their parents when living at home due to convenience and upbringing. However, when these teenagers head off to university they are confronted with a new mix of housemates and differing diets. This, along with their discovery of the price of meat now it is no longer bought in mum’s weekly shop, leads to many people adopting a different diet such as vegetarianism and others. Although dwindling finances and inspiration from housemates are excellent reasons for a dietary change, students may not be fully aware of the comparative environmental cost of each diet.
First to be considered is the meat-based diet. This is the most popular diet in developed countries and consists of an omnivorous mix of meat, seafood, dairy, eggs and plants. All of these foods have different environmental costs associated with them, meaning eating all of them has a huge impact on the environment.
“At least 51% of global greenhouse gas emissions are a result of the livestock industry”
At least 51% of global greenhouse gas emissions are a result of the livestock industry, according to a study by World Watch institute. Livestock, used in this diet to provide both meat and dairy products, contributes 65% of the total release of nitrous oxide into the atmosphere. Nitrous oxide can remain in the atmosphere for 150 years and is 296 times more damaging to the environment than CO2, making this diet worryingly taxing for the planet.
Deforestation is also greatly impacted by the meat industry, with 56 million acres of US land being used to grow crops that are solely fed to animals, compared to the mere 4 million acres of crops grown for human consumption. Using land that was once home to a whole ecosystem drastically reduces biodiversity to only a handful of species.
The pescatarian diet does not include meat from land animals; instead this is often substituted for seafood, resulting in pescatarians eating more fish than the average meat-eater. Many opt for this diet due to its renowned health benefits – the American Medical Association claims that a pescatarian diet cuts the risk of bowel cancer by an alarming 43%. Moreover, removing the consumption of land animals would dramatically decrease the amount of land required to grow crops, however, it could lead to other environmental issues, such as over-fishing.
According to the Food and Agricultural Association of the UN, 31% of all fishing is unsustainable. Unsustainable fishing involves the use of techniques such as dredging, which scrapes heavy metal cages along the sea bed, disturbing all marine wildlife and preventing regrowth of the ecosystem. Additionally, the vast nets that are pulled through the water trap everything in their path, not just the desired species. Trapped dolphins cannot surface for air and subsequently drown, while other fish, killed by the time spent on the boat, are discarded overboard.
“The unsustainable way in which nearly a third of fish are harvested from their marine habitat is causing widespread damage to the underwater environment”
A scandal uncovered by Greenpeace in 2016 exposed that only 2% of the tuna caught for the popular brand John West is fished sustainably, despite being an endangered species. Although most of the fish humans eat are unlikely to become extinct due to the introduction of fish farms, their potential removal from the wild ecosystem would have disastrous knock-on effects for other species.
Overall, the unsustainable way in which nearly a third of fish are harvested from their marine habitat is causing widespread damage to the underwater environment. If this continues, mass extinction will occur to the detriment of both the environment and the consumer.
The 12% of UK residents who are vegetarian go one step further than pescatarians and also remove seafood from their diet, meaning they only consume dairy and plant-based foods. Although the answer may appear obvious, Impact again asked: is this a sustainable diet?
In some respects the vegetarian diet is better for the environment than a diet which includes the consumption of meat. Of the US land assigned for the production of animal products, only 8% is used by the dairy industry, while over 90% is used by the meat industry, according to a 2014 review by Eshel et al. Nevertheless, vegetarian food still contributes to the environmental burden of human eating habits in other ways.
“The average dairy cow requires 4,954 gallons of water per day in the form of their food, water and cleaning”
For example, the water cost of maintaining livestock is extreme. The average dairy cow requires 4,954 gallons of water per day in the form of their food, water and cleaning – that’s over 22 and a half thousand litres! Overusing the 1% of water that is clean enough to drink forces more to be taken from stores. Stores include aquifers, which cannot replenish the water as fast as it is being removed, and fresh water sources like rivers which many species depend on for survival.
Despite this enormous figure, per calorie of product, a vegetarian diet still uses 36% less water than a meat-inclusive diet. Although less than meat, the fact still remains that an estimated 2,300 litres of water is required to produce food for one day’s worth of calorific content for a vegetarian .
So, if the meat, fish and dairy industries are all a death sentence for the environment, surely everyone should join the diet of the 542,000 UK vegans? Unfortunately, it’s not that simple as many vegan staples also carry a hefty environmental price tag.
Take the coconut, an essential component of most vegan diets, often used to replace dairy milk in anything from a curry to a cuppa. Indigenous to southeast Asia, the top three countries the UK receives its coconuts from are Indonesia (roughly 7,300 miles from the UK), the Philippines (6,750 miles from the UK) and India (4, 750 miles from the UK). However it travels, that journey requires a lot of fossil fuels, notoriously detrimental to the environment. An additional environmental setback is that coconut trees are often grown in monoculture. This means that no other crops are grown alongside them, leading to an environment devoid of biodiversity.
“Sadly, soy beans demand a vast amount of land to grow and are responsible for the majority of the 4 million hectares of deforestation in South America every year”
Coconuts are not the only culprit of the unsustainable element of the vegan diet. The beloved avocado thrives in tropical climates, therefore its availability in a non-tropical region requires either a lot of air miles or a lot of water to create a replica growing environment. Soy is another vegan essential; it is used to produce tofu and soy milk as well as a whole host of other products. Sadly, soy beans demand a vast amount of land to grow and are responsible for the majority of the 4 million hectares of deforestation in South America every year.
The solution is moderation, because all of one diet would cause heightened damage to specific aspects of the environment despite helping others. Campaigns such as ‘meat-free Mondays’ are what will really have an impact on the environment. The Environmental Working Group (EWG) states that if a family of four had a vegetarian meal once a week for a year, the reduction in CO2 emissions would equate to not using a car for 3 months. In this era of train strikes it is much more feasible to remove meat from one meal a week than to give up the use of a car for 3 months.
You don’t even need to have a completely meat-free meal to make a massive environmental impact. For example, as the above graph shows, choosing chicken instead of lamb as the backbone of a roast dinner would contribute almost 6 times less CO2. Moreover, substituting tropical products for local, in season produce will also greatly help the environment by reducing air miles.
Simple visual information presented like the above graph should be more widely broadcast instead of pictures of devastating animal abuse which try to shame anyone who isn’t bound to a solely plant-based diet. If information was more accessible and less scare-mongering then it would be more encouraging for people to make environmentally friendly meal choices rather than shying away from propaganda.
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