Vegan Diet: Unhealthy And Unsustainable For Humans

The vegan diet has been labelled as a healthy, sustainable, and cruelty-free alternative to animal agriculture. However, some argue that veganism is not all that it's cracked up to be. While vegan diets have been associated with a reduced risk of cardiometabolic diseases, they have also been linked to adverse health outcomes, such as nervous, skeletal, and immune system impairments, and mental health problems due to potential micro and macronutrient deficits. In addition, the heavy impact of meat and dairy on the planet is well-known, and people in rich nations will have to significantly reduce their meat consumption to combat the climate crisis.

Lack of essential vitamins and protein

A vegan diet is one that excludes all foods of animal origin, including meat, fish, dairy, eggs, and sometimes honey. While there are many health benefits to a vegan diet, it can be difficult to obtain certain nutrients that are abundant in animal products.

One of the main issues with a vegan diet is the lack of essential vitamins and protein. Vitamin B12, for example, is almost exclusively found in animal-sourced foods such as fish, meat, dairy, and eggs. Vitamin B12 is essential for developing red blood cells and maintaining nerves and normal brain function. Vegans who do not take supplements are at a higher risk of vitamin B12 deficiency, which can cause impaired brain function, neurological disorders, and even heart disease.

Vitamin D3 is another nutrient that is more readily available from animal sources. Vitamin D is essential for maintaining bone health and muscle function, and while it can be produced by the body through sun exposure, those with limited sun exposure or who live far from the equator may need to obtain it from their diet. Animal-sourced vitamin D3 is found in fatty fish and egg yolks, while vegan sources include supplements, mushrooms, and fortified foods like cereals and milk.

Protein and amino acid deficiencies are also common in vegan diets. While it is possible to get enough protein from plants, it takes a lot of planning. Plant-based proteins often have lower digestibility than animal proteins due to being encased in plant cell walls. Additionally, some amino acids such as leucine, lysine, and sulfur-containing amino acids like methionine may be lacking in a vegan diet.

Overall, a vegan diet can be sustainable and healthy, but it requires careful planning to ensure adequate nutrient intake. Supplementation with vitamins B12 and D, as well as amino acids and protein, may be necessary to avoid deficiencies.

International transport of fruits and vegetables produces carbon dioxide

Transporting food, especially perishable items like fruits and vegetables, by plane can have a large carbon footprint. However, it is important to note that very little of our food travels by air – only about 0.16% of food miles are from air travel. Most food travels by sea, which has a much lower impact on the environment. Transporting food by air emits around 50 times more greenhouse gases than transporting the same amount by sea. For example, flying one kilogram of asparagus from Lima to London would emit around 11 kilograms of carbon dioxide, whereas transporting the same amount by boat would emit only 0.26 kilograms.

A study by Nature Food found that the carbon footprint of importing food could be up to 7.5 times higher than previously thought. The report estimates that emissions from global food transport are about 3 gigatonnes of carbon dioxide equivalent, which is a much bigger slice of the emissions pie than previously estimated. The study also found that vegetable and fruit consumption makes up over a third of global food-miles emissions. This is because fruits and vegetables often require temperature-controlled transportation, which releases more than three times the amount of carbon dioxide equivalent than ambient transport.

To reduce the carbon footprint of a vegan diet, it is recommended to increase domestic food production in high-income countries and reduce the consumption of imported fruits and vegetables, especially those that are air-freighted or transported long distances by refrigerated lorry or ship.

Tilling of fields releases greenhouse gases and accelerates erosion

Tilling of fields, or tillage, is a conventional farming method where the soil is turned over to prepare the field for planting. However, this practice has been associated with the release of large volumes of greenhouse gases and accelerated erosion.

Tillage disrupts the soil structure, making it more susceptible to erosion by wind and water. This breakdown of the soil structure leads to the loss of fertile topsoil, which can wash away into rivers and lakes, negatively impacting water quality. The residue from tilled fields can also gather in these water bodies, further degrading water quality. Additionally, the disruption of soil ecosystems caused by tillage can result in habitat destruction and a loss of biodiversity, including beneficial insects that provide natural pest control.

Tillage also contributes to increased greenhouse gas emissions. The process releases stored carbon into the atmosphere, specifically carbon dioxide and nitrous oxide, which are greenhouse gases that contribute to global warming and climate change. The disturbance of the soil accelerates the decomposition of organic matter, releasing these stored carbon compounds. Conventional tillage has been associated with a 26-31% higher net global warming potential compared to zero tillage or conservation tillage practices.

Furthermore, tilled fields are more susceptible to weed growth and pest infestations, leading to increased pesticide and fertilizer use. The use of these chemicals can have negative consequences for the environment and human health.

The negative impacts of tillage on the environment have led to the promotion of alternative farming methods, such as e-farming, no-till farming, or conservation tillage. These sustainable farming practices aim to reduce soil erosion, protect water quality, and support biodiversity. By minimizing soil disturbance, no-till farming can help reduce wind and water erosion while also enriching the soil with organic matter. Additionally, no-till farming can reduce fuel consumption and labor costs, as it requires less tractor movement across fields.

Water-intensive crops like avocados and almonds

Similarly, almonds are also water-intensive, consuming 10% of all freshwater resources in California, the state where most almonds are grown. Almond milk, in particular, has contributed to the rise in almond consumption, now accounting for two-thirds of all plant-based milk drunk worldwide. It takes about 12 litres of water to grow a single almond, and almond production uses around 2 trillion litres of water per year, leading to groundwater depletion and land degradation.

The issue of water-intensive crops is not unique to avocados and almonds, and other crops like sugarcane, rice, bananas, and chickpeas also face similar criticisms. However, the popularity of avocados and almonds, driven by their perceived health benefits and the rise of veganism, has led to increased scrutiny of their environmental impact.

To address these concerns, some farmers are taking steps to reduce water use, such as using micro-irrigation systems that apply water directly to tree roots. Additionally, organisations like the Almond Board of California have set targets to reduce water usage in the industry.

Soy crops linked to deforestation

Soy crops have been linked to deforestation in the Amazon Rainforest and the Cerrado, resulting in the loss of over 105,000 square kilometers of native habitat. The Brazilian Cerrado region, Amazon Rainforest, Gran Chaco, and the Atlantic Forest of South America are the major areas at risk from soy-related deforestation. These regions are known for their biodiversity, and deforestation is quickly endangering the animals that call these forests home.

The Cerrado biome, covering 2 million square kilometers in central and northeast Brazil, is home to roughly 5% of the world's biodiversity. However, in recent decades, the region has been at the heart of the world's biggest agribusiness boom, losing roughly half of its original native vegetation as a result.

Brazil, Argentina, and Paraguay are the main producers of soy in South America, with Brazil being the largest producer. The Brazilian government's Prodes deforestation satellite monitoring system found that 220,000 square kilometers in the Amazon and Cerrado biomes were deforested between 2006 and 2017. Of this, 21,000 square kilometers were converted to grow soy, with over 17,000 square kilometers in the Cerrado alone.

The majority of Brazil's soy is produced for export, and the country's soy production is responsible for a significant amount of carbon emissions. The Brazilian government estimates that deforestation for soy cultivation in the country contributes to 29% of its greenhouse gas emissions.

The demand for soy is surging globally, and it is a key source of protein and vegetable oils. Soybeans are used in various food products, such as tofu, soy sauce, meat substitutes, soybean oil, and soybean meal, which is widely used as animal feed. The United States, Brazil, and Argentina together produce about 80% of the world's soy, and China is the largest importer.

While soybean plantations have led to significant deforestation, it is important to note that only a small portion of soy is used for human consumption. Around 70% of the world's soy is fed directly to livestock, and only 6% is turned into human food, mostly consumed in Asia.

To address the environmental impact of soy production, organizations like the World Wildlife Fund (WWF) are encouraging the development of better production practices. The WWF helped establish the Roundtable on Responsible Soy (RTRS) in 2005 to develop solutions for responsible soy production. In 2009, the RTRS adopted preliminary voluntary production standards that prohibit the conversion of areas with high conservation value and eliminate hazardous pesticides in soy farming.

By reducing meat consumption, we can help decrease the demand for soy and, in turn, reduce deforestation. Additionally, improving land-use planning, implementing responsible purchasing and investment policies, and supporting initiatives like the RTRS can contribute to more sustainable soy production practices.

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