Vegan Diets: Sustainable Long-Term?

Veganism is a lifestyle that seeks to exclude all forms of animal exploitation and cruelty, promoting animal-free alternatives for the benefit of animals, humans, and the environment. A vegan diet is plant-based and does not include meat, fish, poultry, eggs, honey, or dairy.

Veganism is widely regarded as better for the planet than diets that include animal products. A study by the French Environment and Energy Management Agency (ADEME) found that vegan diets produced 49.6% fewer greenhouse gas emissions, needed 26.9% less energy for food production, and had a 41.5% smaller environmental footprint than diets that included meat.

However, not all plant-based foods have a small environmental footprint. For example, delicate fruits like blueberries and strawberries are often imported by air to fill gaps when local fruits are out of season, leading to higher greenhouse gas emissions. Similarly, water-intensive crops like avocados, mangoes, and almonds require large amounts of water to grow, putting pressure on local environments.

Vegan diets can also be restrictive and may require careful planning to ensure adequate nutrient intake. For example, vegans are at risk of vitamin B12 deficiency since this vitamin is only available in animal foods. Additionally, vegan diets may result in low zinc status due to higher consumption of plant foods containing phytic acid, which inhibits zinc absorption.

While veganism can be a sustainable long-term lifestyle for some, it requires careful planning to ensure a balanced and nutritious diet.

Nutritional deficiencies

Iron Deficiency and Anaemia

Iron-deficient anaemia is a common issue, and both vegans and vegetarians are at higher risk. Plant foods contain non-heme iron, which is less absorbable by the body. Iron deficiency can lead to fatigue and other serious symptoms, especially in women of childbearing age. While iron supplements can help, they may cause constipation and may not be sufficient to overcome anaemia without animal-sourced iron. Cooking with cast-iron pans can also help increase iron intake.

Omega-3 Fatty Acid Deficiency

Vegans may be at higher risk of depression due to a lack of omega-3 fatty acids from fish or fish oils. Increased consumption of omega-6 fatty acids from nuts can further disrupt the balance of fatty acids in the body. Algae-based omega-3 sources are an option but may be expensive and hard to find. Monitoring omega-3 levels and considering supplements are recommended.

Vitamin B12 Deficiency

Vitamin B12 is only available in animal foods, so vegans are at a much higher risk of deficiency. Most nutrition professionals advise vegans to supplement with high-quality vitamin B12 to avoid irreversible health conditions. Genetic variations, such as the MTHFR mutation, can further impact B vitamin absorption, and supplementation may not be sufficient in these cases. Regular vitamin B12 testing is essential for vegans.

Zinc Deficiency

Vegan and vegetarian diets may result in low zinc status due to higher consumption of plant foods containing phytic acid, which inhibits zinc absorption. Nutrition professionals often recommend that vegans and vegetarians increase their zinc intake by up to 50% of the recommended daily allowance to maintain adequate levels. Good zinc levels are crucial for a healthy immune system.

Iodine Deficiency

Vegan and vegetarian diets may not provide sufficient iodine due to the exclusion of seafood. Iodine deficiency can lead to hypothyroidism and other health complications. Supplementation with iodized salt or seaweed products can help, but deficiencies may still persist.

Calcium Deficiency

Vegan diets may not provide enough calcium, as plant-based sources typically contain lower amounts than dairy products. Additionally, phytates and oxalates in plant foods can inhibit calcium absorption. Long-term calcium deficiency can increase the risk of bone fractures. Fortified plant-based milk or calcium supplements can help prevent this deficiency.

Protein Deficiency

Vegan diets can be lower in protein, leading to fatigue and low exercise tolerance. Finding quality protein sources that are not also high in carbohydrates can be challenging for vegans. Protein powder supplements may be necessary to ensure adequate protein intake.

In conclusion, while a vegan diet can be sustainable long-term for some individuals, careful planning is required to avoid nutritional deficiencies. Regular consultation with healthcare professionals and supplementation may be necessary to maintain optimal health on a vegan diet.

Environmental impact of food production

A vegan diet is widely regarded to be better for the planet than diets that include animal products. However, not all plant-based foods have a small environmental footprint.

Meat, especially beef, has an unsurpassable contribution to the planet's greenhouse gas emissions. It also devours more land and water and causes more environmental damage than any other single food product. Even the "greenest" sources of meat still produce more greenhouse gases than plant-based proteins.

However, some plant-based foods also come with a heavy price tag. For example, delicate fruits like blueberries and strawberries are often imported to Europe and the US by air to fill gaps when local fruits are out of season. Similarly, avocados, mangoes, and plums are water-intensive crops. Cocoa and raw cacao products are also major drivers of tropical deforestation.

Overall, a vegan diet can be more sustainable in the long term, but it is important to be mindful of the environmental impact of specific plant-based foods and to choose locally produced and in-season options whenever possible.

Health benefits

A vegan diet is associated with several health benefits.

Firstly, vegans have a lower prevalence of overweight and obesity and a lower risk of heart disease compared to non-vegetarians from a similar background. Research has also shown that vegan diets are linked to a lower risk of type 2 diabetes, with a study from the Adventist Health Study-2 cohort showing that the risk of self-reported diabetes was approximately halved in vegans compared to non-vegetarians.

Secondly, vegans have been found to have lower risks of diverticular disease and eye cataracts. Additionally, there is some evidence that the risk for all cancer sites combined is slightly lower in vegans than in non-vegetarians.

Finally, overall mortality is similar for vegans and comparable non-vegetarians, but vegans compare favourably with the general population.

However, it is important to note that a vegan diet can be restrictive and careful planning is required to ensure adequate nutrient intake, especially for vitamin B12, vitamin D, calcium, and omega-3 fatty acids.

Longevity

There is extensive research into the nutritional adequacy of vegetarian diets, but less is known about the long-term health of vegans. One study found that vegetarians have a lower prevalence of overweight and obesity and a lower risk of heart disease compared with non-vegetarians from a similar background. They also have lower risks for diabetes, diverticular disease and eye cataracts. Overall mortality is similar for vegetarians and non-vegetarians, but vegetarian groups compare favourably with the general population.

However, vegans are at a much higher risk of developing a vitamin B12 deficiency, as it is only available in animal foods. This can lead to irreversible health conditions. Vegans are also at a higher risk of iron-deficient anemia, as plant foods contain non-heme iron, which is much less absorbable by the body.

There is also a risk of not consuming enough iodine and calcium on a vegan diet, as well as too many carbohydrates and not enough high-quality protein.

Overall, a vegan diet can be sustainable long-term, but it requires careful planning to ensure you are getting all the necessary nutrients.

Sustainability

Veganism is a philosophy and way of living that seeks to exclude all forms of animal exploitation and cruelty. It promotes the development and use of animal-free alternatives for the benefit of animals, humans, and the environment.

Veganism is widely regarded as better for the planet than diets that include animal products. A study by the French Environment and Energy Management Agency (ADEME) found that vegan diets:

• Produced 49.6% fewer greenhouse gas emissions
• Needed 26.9% less energy for food production
• Had a 41.5% smaller environmental footprint compared to diets that included meat

However, not all plant-based foods have a small environmental footprint. For example, almonds and cashew nuts are some of the most water-intensive large-scale crops grown. Almonds need large amounts of water, pesticides, and fertilizers, which makes their environmental impact disproportionately large.

Another example is asparagus, which has a high carbon footprint due to it often being imported by air from Peru to the UK. Similarly, avocados are grown in water-stressed regions and need a lot of water, putting huge pressure on the local environment.

Some people argue that veganism is not natural for humans and that most people cannot stick with it. However, this is not necessarily true. There are many people who have been vegan long-term without any concerns.

Veganism can be a very restrictive diet, and careful planning is required to ensure that individuals get all the nutrients they need, such as iodine, zinc, calcium, omega-3 fatty acids, and vitamin B12. Fortified foods or supplements are often necessary to provide these nutrients.

Overall, veganism can be sustainable long-term, but it requires careful planning to ensure that individuals get all the necessary nutrients.

Frequently asked questions