A vegan diet eliminates all animal foods, including meat, fish, dairy, eggs and, for stricter vegans, honey. The diet consists solely of plant-based foods such as fruits, vegetables, grains, beans, pulses, nuts and seeds.
The decision to undertake a vegan diet can be made for ethical, environmental and/or health reasons. The production of animal products is highly labour-intensive and produces significantly higher greenhouse gas emissions than plant-based foods, with a recent study showing that animal products account for 57% of all greenhouse gases from food production.
As a way of comparison, the researchers found that 2.5kg of greenhouse gas emissions are created to produce 1kg of wheat, whereas 70kg of greenhouse gas emissions are created to produce 1kg of beef (1). At a time when the threat of climate change is paramount, more and more people are turning to veganism as a more sustainable way of living.
Vegan diet benefits
As well as reducing the impact on the environment, a vegan diet can provide many health benefits.
Studies amongst vegetarians and vegans have shown lower levels of heart disease, reduced incidence of certain cancers, and a reduced risk of developing type 2 diabetes than meat eaters. This is likely due to vegans and vegetarians being found to have a lower body mass index (BMI), lower blood pressure, lower levels of inflammation and lower glucose levels (2). A 2018 study in the Journal of Clinical Cardiology (3) found that when patients excluded all animal products for just four weeks, it resulted in a significant reduction in blood pressure and cholesterol levels.
A more practical benefit of adopting a vegan diet is that it is a great opportunity to improve your diet in general by including many more nutrient dense plant-based foods, experimenting with new dishes and putting a plant-based twist to some of your current favourite meals. Plant-based foods are packed with a variety of vitamins, minerals, phytochemicals, antioxidants and fibre, which bring a whole host of health benefits for the body to function at its best. Eating a broad variety of plant-based foods has also been linked to improving the diversity of healthy gut bacteria. When an individual’s gut bacteria (known as their gut microbiome) is in good balance, it can positively influence digestion and immune function, as well as new emerging research showing it influences other areas like weight control and mental health.
Is being vegan healthy?
The above health benefits are only relevant if the quality of the vegan diet is good, which means taking a whole food approach and ensuring that all nutrients are covered is key. A little planning is required as there are some nutrients that are harder to find in plant-based foods alone, but once you’ve got it covered, a vegan diet can provide you with all the nutrition you need.
One of the most common mistakes that people can make on a vegan diet is eating too many processed vegan products. Vegan alternatives and treats are abundant, but just because they’re marketed as plant-based doesn’t make them nutritious or healthy!
How to get protein as a vegan
The best vegan sources of protein are beans, lentils, chickpeas, tofu, nuts, and seeds. Some wholegrains and vegetables also contain some protein. It is easy enough to get enough protein from plant-based sources, as long as you eat a whole food diet containing a variety of the above-mentioned foods. This is because not all of them are classed as complete proteins.
Protein is made up of individual components called amino acids - some amino acids can be made by the body, and some come solely from the food you eat. These are known as essential amino acids, of which there are nine. Most plant-based sources are incomplete proteins meaning that they don’t contain all of the nine essential amino acids. Incomplete protein sources are legumes, pulses, nuts, some seeds, wholegrains, and some vegetables. Soy (including tofu), quinoa and some seeds such as chia and hemp are complete protein sources, meaning that they contain all of the essential amino acids. This doesn’t mean that incomplete protein sources are low in protein - on the whole they are still excellent sources, it may just mean that one or more amino acids are lacking in that particular food.
This is why it is important to consume a variety of plant-based protein foods throughout the day. If you eat a whole food plant-based diet, this will be easy to achieve. Protein powders based on pea and hemp protein can provide additional protein to the diet, and may be useful for vegan athletes who have higher protein requirements, however they are not necessary in the majority of vegan diets.
What supplements should vegans take?
As a general rule, it is always recommended that you get your nutrients from food first. However, in a vegan diet, vitamin B12, iodine, selenium and vitamin D can be especially difficult to obtain from plant sources alone, so taking a few good quality supplements is important to avoid any health problems resulting from deficiencies. You can find these nutrients in fortified foods such as dairy-free milks, but not usually in the amounts that are necessary.
Vitamin B12 is important for healthy blood, the brain and the nervous system. It is also a component in making DNA, which is found in every cell of the body. It is only found in sufficient amounts in animal sources, therefore a daily supplement must be taken.
Iodine is important for healthy thyroid function to ensure your body’s metabolism is working efficiently. It is found in seafood and dairy products. It can also be found in seaweed but in unreliable amounts, so supplementation is advised.
Selenium is important for many functions such as reproductive health, thyroid health and the creation of DNA. It also has an antioxidant effect in the body. Brazil nuts can be a great source of selenium, however the amounts can vary considerably depending on the soil where they were grown. The only other sources of selenium are seafood and meat, therefore a supplement that contains selenium is recommended.
Last but not least, many people are already low in vitamin D due to its main source being sunlight. Vitamin D is important for healthy bones and muscles, regulating cell growth, mental health, cardiovascular health and good immune function. Vegans are more at risk of deficiency as its only real food sources are oily fish and eggs. There is a small amount in mushrooms, but not enough to be relied upon. Therefore, in the winter months especially, it is important to supplement with vitamin D.
As you can see, a vegan diet can be very beneficial for your long-term health, and the environment, with the right planning, preparation and supplementation.
A few other nutrients to watch out for on a vegan diet are calcium, zinc and omega 3 fats, however these can be easily obtained from plant based-foods as long as you take a whole food approach. Calcium, for example, can be found in tofu, leafy green vegetables, sesame seeds, figs, oranges, almonds and fortified milks. Zinc, necessary for its role in immune health and efficient metabolism function, can be found in legumes, nuts, seeds and wholegrains. Omega 3 fats can be found in chia seeds, flax seeds and walnuts, so be sure to have a portion of one of these a day for their heart-healthy, anti-inflammatory properties.
A good tip is to make a checklist of all the above-mentioned foods to have on-hand for meal planning and shopping. Like anything, it will also get easier the more that you get used to it, and if you need help, then seeing a nutritionist can provide you with further guidance. If you do decide to adopt a vegan diet (or just eat predominantly more plant-based), enjoy the process, have fun with new recipes and connect with like-minded people to share recipes and experiences.
- Global greenhouse gas emissions from animal-based foods are twice those of plant-based foods
- Plant-based diets: Considerations for environmental impact, protein quality, and exercise performance
- A defined, plant-based diet utilized in an outpatient cardiovascular clinic effectively treats hypercholesterolemia and hypertension and reduces medications