As Veganuary approaches, many people will be making the switch to a plant-based diet to counteract the indulgences of the festivities. Many people have already chosen to exclude animal foods from their diet, both for ethical and health reasons.
A whole foods, plant based diet can be health promoting, being high in fibre, antioxidant rich vegetables and low in saturated fats. However, there are certain nutrients which can be lacking from a vegan diet, one of which is vitamin B12.
What is vitamin B12 and where can it be found?
B12 – Cobalamin – is a water soluble vitamin which is part of the B complex family.
There are various forms of cobalamin: with methylcobalamin being the active form and cyanocobalamin being the synthetic form.
B12 is found only in foods of animal origin. The main sources are: meat, fish, eggs and dairy.
Vitamin B12 is synthesised by bacteria, including those in human colon, however the vitamin produced by human colon bacteria is not absorbed.
In adequately nourished individuals, the vitamin can be stored (in the liver) for up to 5 years.
People consuming animal products are unlikely to encounter issues of low B12, although some people are more at risk of insufficiency; such as elderly people, pregnant women, vegans and vegetarians, and people taking certain medication such as PPI inhibitors, metformin, histamine 2 receptor antagonists and chloramphenicol). Individuals suffering from pernicious anaemia may also be at risk of vitamin b12 deficiency due to malabsorption of the nutrient.
What are symptoms of B12 deficiency?
Vitamin B12’s key role is the function of the nervous system, but also play a role in cardiovascular health, DNA production, and energy production.
If suffering from insuffiency, you may experience symptoms such as:
- Fatigue and weakness
- Lack of appetite
- Neurological symptoms such as numbness or tingling of extremities
- Mouth and tongue soreness
If this insuffiency persists, you may experience deficiency symptoms such as:
- Confusion
- Poor memory/ dementia
- Balance issues
- Nerve damage
Please note that if left untreated, vitamin B12 deficiency can cause irreversible nerve damage.
If you are simply avoiding animal products for the month of January, it is unlikely you will need to supplement with B12. However, if you are considering a long-term, strict vegan diet which excludes all foods of animal origin, I would highly recommend supplementing with B12 in the active form of methylcobalamin. This general daily dose is 1-25mcg a day; however, you may supplement up to 100mcg a day to normalise a deficiency. As the vitamin is water soluble, it is considered non-toxic in higher doses, both in food or in supplemental form. Taking a sublingual form or chewing your supplement slowly will increase absorption.
Pregnant and lactating vegetarian/ vegan mothers should have their serum vitamin b12 status, along with homocysteine and folate regularly checked throughout the pregnancy. Supplementation as well as consuming b12 fortified foods is also advised.
If you would like some advice on how to transition to a plant-based diet, please BOOK A FREE DISCOVERY CALL to see how nutritional therapy can help you achieve your goals.
References:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5188422/
http://www.whfoods.com/genpage.php?tname=nutrient&dbid=107
https://www.ebmconsult.com/articles/vitamin-b12-medication-interactions-lower-levels
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5273828/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6470702/
