There are many benefits to the vegan diet over one that includes meat. Vegan diets have less saturated fats and protein in their diet. This lightens the load on the digestive system and the heart. Also, vegans tend to have a higher intake of fibre, complex carbohydrates and most minerals and vitamins; which brings a range of positive contributions to health. In addition, there are many studies showing that vegan diets are better for the environment, when you consider greenhouse gas emissions, land use, freshwater use and water pollution (Poore and Nemecek, 2018).
However, if one is to go completely vegan then there are valid concerns for potential nutritional deficiencies. This article will outline some of the key concerns around protein deficiency, blood sugar levels, EFAs, essential minerals and vitamins.
Protein Deficiency
Protein is one of the major macronutrients. Learn more about protein here.
Proteins from animal sources are often termed complete proteins, as they contain all the essential amino acids. Whereas, proteins from plant sources don’t contain all the essential amino acids. However, vegans can overcome this through combining complementary proteins. This is where two or more proteins combined contain all the essential amino acids. For example, grains have the limiting amino acid lysine and pulses are high in lysine. The combination of these two will ensure your body has all the amino acids present. I would advise having these in the same meal, so it becomes second nature and you are sure that you’re getting good quality protein. However, as long as it is eaten the same day than it is fine.
Blood Sugar Difficulties
Often a vegan diet is higher in carbohydrates, which can lead to a disturbance in blood sugar levels. Read more about carbohydrates and blood sugar levels. Meat doesn’t have any carbohydrates in it. So naturally by replacing the meat quantities with other foods there will be an increase in carbohydrates in the diet. It’s important to think about the type of carbohydrate being consumed. Refined carbohydrates (such as white bread or white pasta or white potatoes) will cause spikes in blood sugar levels, as they are digested and turned into glucose quicker due to their previous processing. Whereas, complex carbohydrates (like quinoa, brown rice or oats) will take longer to digest and lead to a slow release of energy.
Vegan Substitutes
Products such as soy and quorn can be high salts, which isn’t good to ingest in high quantities. For example, two Linda McCartney vegetarian sausages have 1.2g of salt; which is already 20% of your maximum daily allowance. Therefore, it’s important to not solely rely on vegan replacement products, such as vegetarian sausages or burgers.
Fruit & Vegetable Intake
It’s very important to ensure that you’re getting a range of nutrients from fruit and vegetables every day, because as a vegan you have a more limited pool in which to gain nutrients from. I would recommend at least 5 vegetables and 2 fruits a day. Check out my resources section for some great handouts to make sure you’re eating rainbow.
Essential Fatty Acids (EFA)
Some fats are termed ‘essential fatty acids’ (EFA) as the body can’t produce them (Mann and Truswell 2012). This means that humans are reliant on them from their diet. There are two essential fatty acids for humans – omega 3 (alpha-linolenic acid (ALA)) and omega 6 (linoleic acid).
What are good vegan sources of these EFAs?
Omega 6 | Omega 3 |
Hemp seeds Pumpkin seeds Sunflower seeds Walnuts Soya Spread Vegetable Oils | Chia Seeds Ground Linseed Hemp Seeds Walnuts |
It is important to get the right balance between these two families of EFA, as they work in tandem. For instance, if you eat a lot of omega 6, your body may convert less omega 3 into EPA and DHA, reducing the amount of omega-3 fat in your blood. This is because they compete for the same enzyme that processes them. Ideally one needs a 1 to 1 ratio (Simopoulos, 2002).
Vitamin Deficiencies – B12
Vitamin B12 deficiency is an especially important issue for vegans; as it is mostly obtained from animal sources. B12 is very important for methylation in the body; which is needed to convert neurotransmitters for optimal brain functioning and for liver detoxification. It also works with folic acid in many bodily functions, including the synthesis of DNA (Murray et al., 2008). Thus, a deficiency of vitamin B12 will result in a folic acid deficiency too.
The RDA for B12 is 1.5mg in the UK (Public Health England, 2016). It is often cited that vegans can obtain B12 from brewers yeast or fermented foods such as tempah. However, there is a large variation in the B12 content in foods and there is some evidence that it isn’t in the form that the body needs (Murray et al., 2008).
Mineral Deficiencies – Iron
Iron deficiencies can also occur, as plant based sources of iron aren’t absorbed as well as animal based sources. Iron plays a central role in the haemoglobin molecule of our red blood cells, where it functions in transporting oxygen from the lungs to the body’s tissues and carbon dioxide from the tissues to the lungs. It is also vital for several key enzymes in energy production and metabolism including DNA synthesis (Murray et al., 2008).
Mineral Deficiencies – Calcium
Although calcium is present in many fruits and vegetables, most people in the UK get their main source from dairy. The EPIC Oxford trial found that vegans had a 30% higher risk of fractures than non vegans. However, with vegans who had an adequate calcium intake there was no difference. An easy way to ensure regular calcium in your diet is through using nut milks (which are fortified with calcium) in place of when you would use dairy milk – these have similar calcium contents.
This article gives an overview of the key nutritional concerns to consider if deciding to take on a vegan diet. If you would like more tailored and expert diet advice then submit an enquiry form.
SOURCES:
Ballentine, R., 2007. Diet & Nutrition. 2nd ed. Honesdale: Himalayan Institute.
Poore, J. and Nemecek, T., 2018. Reducing food’s environmental impacts through producers and consumers. Science, 360(6392), pp.987-992.
Public Health England, 2016. Government Dietary Recommendations. Government recommendations for energy and nutrients for males and females aged 1 – 18 years and 19+ years. London: Public Health England.
Mann, J. and Truswell, S., 2012. Essentials Of Human Nutrition. 4th ed. Oxford: Oxford University Press.
Murray, M., Pizzorno, J. and Pizzorno, L., 2008. The Encyclopaedia Of Healing Foods. 1st ed. London: Piatkus.
Simopoulos, A., 2002. The importance of the ratio of omega-6/omega-3 essential fatty acids. Biomedicine & Pharmacotherapy, 56(8), pp.365-379.
The Vegan Society. 2021. Statistics. [online] Available at: https://www.vegansociety.com/news/media/statistics#:~:text=please%20visit%20here.-,Veganism%20in%20the%20UK,150%2C000%20(0.25%25)%20in%202014. [Accessed 3 January 2021].
Disclaimer: This blog is for information purposes. It is not medical advice. The statements on this blog are not intended to diagnose, treat, cure or prevent any disease. The material on this website is not to be used by any commercial or personal entity without expressed written consent of the blog author.