Our consumption of food has a significant environmental impact. The effects vary greatly depending on the vegan diet with vegetarian diet. So, the purpose of this post is to find out which diet has the minimum negative influence on the environment. This includes a comparison of a vegan diet with vegetarian and omnivorous diets.
Most of the studies include a direct focus on the environmental effects of human diets.
Moreover, the investigations last anything from 7 days to 27 years. Since the majority of the experiments conducts in the United States or Europe. Our findings imply that the vegan diet with vegetarian diet is best for the environment. Because all diet studies produce the least amount of greenhouse gas emissions.
Further, the analytical research shows that it is possible to achieve the same environmental impact. As a vegan diet eliminate meat and dairy foods completely. Rather by lowering them.
By 2050, the world’s population expects to reach 9.8 billion, as per the UNO. Considering the existing population of 7 billion, this figure represents an almost 30 % expansion.
Demographic variations & population expansion mean that demand for animal goods is rising. Especially meat, dairy items, and crops, which suppliers must meet.
Meat & milk production predicts to grow by 73 & 58%, by 2050. Issues regarding animal welfare exists for generations. But climate change & greenhouse gas emissions recently gaining momentum.
Industrial food sectors(agriculture), have a very unsustainable environmental impact. The use of natural resources such as water, land, & fossil fuels raise animals & grow crops. That in turn, contributes to environmental degradation.
Agriculture alone is responsible for 10–12% of global GHG emissions. By 2030, it expects that GHGs increases by up to 150% from the present levels.
As final outcomes, finding strategies reduce the negative effects of climate change. And the environmental impact of the ongoing food system turns increasingly important.
Although a sustainable diet is one that is nutritionally balanced, safe, healthful, culturally accepted. Also economically feasible, with minor environmental impact. It protects & respects biodiversity as well as ecosystems.
What is LCA?
While there is no common mechanism for quantifying these consequences. Then the Life Cycle Impact Assessment technique (LCAs) is a commonly applied tool.
It helps in calculating the environmental effects of food production, transportation, waste disposal, storage, processing & other life phases.
Vegan diet with Vegetarian diets exclude all animal foods, including meat, dairy, and eggs;
LOV stands for lacto-ovo-vegetarian diets which include
• Dairy products
But exclude animal meat; and
OMN stands for omnivorous diets which include:
All animal foods, including eggs, dairy,& meat.
Greenhouse Gas Emissions of Various Diets
In terms of carbon footprint, red meat production accounts for 23 % of agriculture GHGs. Generally, GHGs include CO2, CH4, & NO2.
GHGs from agriculture results in an increase, causing changes in land use(deforestation). NO2 & CH4 emissions from livestock contribute to 80 % of all agricultural GHGs.
Enteric fermentation is useful for cows & manure management. Usually, account for around 31% of CH4 emissions in the US.
Sometimes, the amount of emissions per unit of livestock product differs depending on the animal. Herbivore livestock- cattle, sheep, & other animals, appears to emit more GHGs than poultry or pigs.
Although it is responsible for roughly 44% of total worldwide CH4 emissions. Yet beef production dominates the output. For every kg of beef production, 43 kilos of GHGs released. CH4 emissions account for about 22 kg of the 43 kg in total. Hence, this finding doesn’t include the GHGs from the beef carcass.
Before the final consumption, it generates a large portion of GHGs in the supply chain. Meat production produces more GHGs than LOV & vegan diet production.
Another study of beef production needs 42x more land, 2x more water. Also, absorbing 4x more nitrogen per gram of protein in the human diet. While generating 3x more GHGs than a basic plant diet.
Finally, an Indian study states, mutton & milk production accounts for up to 23% & 35% of total local agricultural GHGEs. Whereas all other food production accounts for only 16%.
GHGs influenced by cattle production. They also pose a serious threat to our world. Since another study claims, dairy & meat processing operations contribute 80 % of all GHGs & 24 % of total GHGs in the food industry. Cheese & meat manufacturing account for over 40% of daily GHGs.
Herbivore animals emit the highest amount of GHGs per gram of protein/calories. Primarily GHGs made up of CH4.
According to self-report dietary patterns in the UK,
• heavy meat consumers were accountable for 1.9 times
• average meat consumers were accountable for 1.5 times more GHGs than persons on LOV diets, while
• vegan consumers were accountable for 2.5 and 2 times more GHGs, respectively.
One of the following studies states that if the consumption quantity of European diet(poultry, pig, dairy, beef) were cut in half. Next, swap with a 50 % increase in bread consumption. Then the amount of GHGs generation is lower by more than 1/3rd of total GHGs emissions.
Numerous studies find that diets with excessive quantities of ruminant meat intake have higher levels of GHGs.
A correlation of environmental impact & diet quality is shown by Walker et al. It appears that eating fewer animal items as well as eating more vegetables results in lower GHGs.
Several other studies find that increasing the amount of animal-based food in one’s diet has an adverse effect on the environment. Diets that are low in meat/processed foods intake have lower GHGs than those that are high in the respective category.
Land Use Pattern for All Three Diets
Beef production demands far more resources than the production of staple plant staples. That includes potatoes, beans, and grains. According to one study, 1 kilogram of beef requires
• First, 163 times the amount of land,
• 18 times the amount of water,
• And 19 times the amount of nitrogen, or
• 11 times the amount of CO2
Then 1 kg of rice or 1 kg of potatoes. According to another study, meat production contributes 39 % of land use connection to human food.
Furthermore, a non-vegetarian diet requires
• 2.9 times extra water
• 2.5 times extra primary energy
• 13 times extra fertiliser
• 1.4 times extra pesticides
than a LOV diet. In addition, animal farming consumes 70% of the total agricultural area. And 1/3 rd of cultivable land. As a result, it plays a significant role in CO2 emissions & habitat destruction due to deforestation.
Protein conversion efficiency varies by animal type: chicken broilers have an 18% conversion rate. Whereas pork & beef have 9 percent & 6 percent, respectively.
Resulting in the land demands for animal protein varying from those for plant-based protein. Because it uses more feed for a similar amount of animal-source protein. In contrast to soybeans as a protein source, it is obvious that animal protein requires 6 to17 times more land.
Water Consumption As Per the Diet
Generally, water scarcity is also a result of livestock rearing. To meet the growing demand for livestock products, it primarily relies on finite irrigation water. Animal agriculture contributes 12% utilization of all surface water & groundwater for irrigation.
Now, the outcome is that the entire water footprint amounts to 29 % of global agricultural output. According to one study, a diet with a smaller proportion of cattle products decrease world water usage.
Sometimes, the amount of water used determines through variations in seasonal and annual rainfall. Meat manufacturing consumes more water in comparison to plant protein production.
Under one study there is variation in water intake for animal protein v / s plant protein. Usually approx. a factor of 26. Even when intense irrigation is important for plant & animal protein production. Taking 4.4 times the amount of water.
A second study backs up this conclusion, claiming that the manufacture of LOV diets raises the water shortage footprint by 26%. However, general scientific conclusions are hard to make. Because studies on water use indicators rely on very little evidence.
Each kilogram of consumable beef takes approximately 13 kilograms of grain. Or 30 kilograms of hay, which demand 105,400 liters of water. Additionally, one kg of crop demands 500 to 2000 lt of water. The essential intake is to create 1 kcal of plant protein is 2.2 kcal. Particularly in terms of usage of fossil energy during the process.
Environmental Impact of Omnivorous Diet
A Swedish study evaluating beef to soybeans find that beef takes 18 times higher energy. Also generates 71 times more CO2 per gram of protein in comparison to soybeans.
If the caloric & nutrient value of the meal ignores and the production of the vegetarian alternative has a connection with greater GHGs. Then replacing emissions cheese for chicken in a diet may lead to higher cumulative GHGs emissions.
Transportation particularly the long-distance, frozen, & other horticulture practices are also crucial variables. All of which might cause more environmental damage than local organic beef.
While the total quantity of CO2 produced by vegetarians & partially vegetarians is an average calorie intake, another study states that 2000 kcal. Simply resulting in a 3.81 kg CO2 equivalent.
Environmental Impact of a Vegetarian Diet
González-Garcia et al. looks at how eating habits differ around the world. Even among the vegan diets with vegetarian diets. They point out that some LOV diets include fish & even meat on unusual occasions. That is the big difference among these diets linking to calorie consumption, specific food options, & national dietary recommendations.
Confining the research studies of LOV includes animal products. Excluding the animal products such as eggs, cheese, milk. But also excludes any sort of meat.
Several Environmental Effects of a Vegan Diet
As per one study, heavy meat-eaters in the United Kingdom had 1.9 times more GHGs than a LOV. Whereas medium meat-eaters had roughly 1.5 times more. And, heavy meat eaters’ food relates to 2.5 times more GHGs than a vegan’s. While average meat-eaters are responsible for twice as many GHGs.
Similarly, another study finds results on the basis of the consumption of 2000 kcal in various diets:
• 7.19 kg for high meat-eaters
• 5.63 kg for medium meat-eaters
• 4.67 kg for minimal meat-eaters
• 3.81 kg for vegetarians
• 2.89 kg for vegans
In an LCA report, if beans swap for beef, then 692,918 km2 of US agriculture save for other purposes. Also, the GHGs from this area reduces by 74%. According to Perignon et al., if all dairy & meat products replace with plant foods, then the land consumption decreases by 50%.
Fruits & vegetables make up a big component of plant diets. Because the origin and mode of transit of these items have a huge impact on their contribution to GHGEs, which can vary greatly.
It makes a big difference whether they grow in heated greenhouses or not. However, the local cultivation & selling of Fruits/vegetables are more eco-friendly.
Evidence, on the other hand, demonstrates that this is not the case. In a study, customers in the United Kingdom who drive more than 7.4 kilometers buy locally. Grown vegetables & fruit have higher GHGs emissions than if the product delivers via a wide network delivery service closer to the customer.
• The GHGEs vary significantly depending on the vegan diet, with a vegan diet producing the least CO2 equivalent per 2000 calories taken.
• Probably three diets have different environmental effects on land & water.
• Usage of animal proteins in OMN and LOV diets also increases water consumption.
• In other words, the larger the amount of animal protein in a diet, then there is more usage of the water.
• A diet consisting only of plant foods has the greatest potential for reducing global water usage. In addition, animal farming consumes 70% of the total agricultural area. While a 1/3 rd of farmland is useful in animal farming. On this basis, a vegan diet uses the least amount of water & land of the three diets.
• Finally, a completely vegan diet has the least negative influence on the environment. As an outcome, this review adds to the growing body of research. That is recommending a shift to a more sustainable food system & consumption.
• However, it’s worth noting that, in order for a 100 percent vegan diet to be sustainable. Then you should choose the local items with low transportation effects.
More research should be done on the production of GHGs by various types of vegan diets with Vegetarian diets. As well as altered omnivorous diets that have a similar environmental impact as a vegan diet.