Nutritional considerations on a vegan diet
Written by Aishah Angell @goodnutrients
Veganism is a popular diet that more and more people follow every day. A vegan diet is a plant-based diet free from animal products including meat, seafood, dairy, eggs and honey. The main factors that motivate individuals to become vegan surround the environment and animal ethics. If you are thinking about switching to a vegan diet, it is important to consider that there are some key nutrients of utmost importance as they are found mainly in animal products. Another thing to consider is that vegan processed foods can be quite high in salt, sugar and fat, so it is important to be mindful when consuming these foods. This is not to say, however, that you cannot get all the nutrients that you need from a vegan diet, you just need to be organised!
Nutrients to be aware of:
· Protein is involved in metabolism and tissue growth and repair in the body.
· It is made up of 20 amino acids (the building blocks of protein), 9 of which can only be obtained through the diet (essential amino acids).
· Animal sources of protein (such as fish, eggs, chicken, or beef) contain all 9 essential amino acids whereas most plant-based sources of protein contain only a few essential amino acids (apart from soy, quinoa and mycoprotein). Therefore, it is important to eat a variety of plant-based food to combine protein sources in order to get all 9 essential amino acids.
· Vitamin B12 is important for nervous system function and making red blood cells, so a deficiency can lead to vitamin B12 anaemia.
· Vitamin B12 is found in animal products including eggs, fish, chicken, beef and dairy products. However, some plant-based milk and breakfast cereals are fortified with vitamin B12.
· You could consider taking a vitamin B12 supplement if you are vegan as it can be tricky to hit the daily recommended amount of 1.5 micrograms.
· Iron is essential to produce haemoglobin, a protein in the blood that transports oxygen around the body, is involved in immune function and metabolism.
· The 2 main forms of iron are non-haem (from plant-based sources) and haem iron (from animal sources). Haem iron is more readily absorbed by the body compared to non-haem iron.
· However, the absorption of non-haem iron can be improved if you consume a source of vitamin C at the same time. Consuming caffeine alongside non-haem iron can prevent absorption.
· Sources of non-haem iron include dark green leafy veggies such as kale or spinach, wholegrains, lentils, tofu, chickpeas, chia seeds and flaxseeds.
· An iron deficiency can result in anaemia, which can leave you feeling dizzy and fatigued. If you are unsure about your iron levels, it is important to see your GP before taking an iron supplement as an excess intake can have adverse health effects.
· Calcium is essential for bone and dental health and muscle contractions and mainly found in dairy products. Plant-based sources include broccoli, fortified plant-based milk, fortified flour and tofu.
· A calcium deficiency can lead to osteoporosis later in life.
· Vitamin D is a fat-soluble vitamin, essential for calcium absorption and therefore healthy bones and teeth.
· Vitamin D is also known as the sunshine vitamin as we can absorb vitamin D via exposure to UV rays. Dietary sources of vitamin D are limited but include egg yolks, fatty fish and fortified foods. In the UK, exposure to sunlight is limited to certain months of the year which is why it is recommended that all adults in the UK take a 10 microgram vitamin D supplement from October-March, and this is especially important for those following a vegan diet.
Omega-3 fatty acids
· Omega-3 fatty acids are a type of polyunsaturated fat (EPA, DHA, ALA) important for increasing good cholesterol levels and heart health. ALA, DHA and EPA are the 3 types of omega-3 fatty acids – EPA and DHA are found in fatty fish such as mackerel, salmon, trout and herring. ALA must be converted to EPA and DHA before it is used by the body so is less efficient than consuming sources of EPA and DHA. ALA is found in plant sources such as linseeds, chia seeds, hemp and walnuts.
· Iodine is important for the formation of thyroid hormones. The best food sources of iodine include fish and shellfish. Iodine can be found in fortified plant-based products such as milk and cereals but iodine content in vegetables varies depending on the soil they are grown in. If you are considering following a vegan diet, you could consider taking an iodine supplement but it important that you contact your GP before doing so as an excess intake of iodine can have adverse effects on your thyroid glands.
For specific health concerns surrounding a vegan diet, please see a registered nutritionist or dietitian. Book a free call to see how we can help you.
This blog post was written by Registered Associate Nutritionist Aishah Angell who graduated from the University of Leeds with a BSc in Nutrition. Aishah currently works in London as a health advisor giving individuals diet and lifestyle advice to improve their health. You can find Aishah on Instagram @goodnutrients where she posts easy recipes, balanced lifestyle tips and evidence-based nutrition. She grew up in Singapore and aims to incorporate her Asian heritage with her passion for health on her page.