Last week I mentioned the vitamins and minerals that vegetarians and vegans must pay attention to in order to ensure all nutritional needs are met; iron, b12, iodine, calcium, zinc, and vitamin D. These are particularly important to those who follow a plant-based diet because animal products tend to be the predominant source, the bioavailability is higher in animal products, and are more easily absorbed. This week, lets dive into the importance of B12!
“Vitamin B12 is produced by soil microbes that live in symbiotic relationships with plant roots¹.” B12 is a member of the vitamin B complex; is necessary for the synthesis of red blood cells, the maintenance of the central nervous system, and DNA synthesis and growth.
B12 Plant Sources
Vitamin B12 found in animal products actually comes from the soil that animals consume while grazing. So in the past it is believed that humans were able to obtain B12 through contact with soil, such as the bacteria remaining on fruits and vegetables after harvest. Today, livestock is seldom pasture-fed (grass fed) and instead are provided with previously manufactured “animal feed”. Because these manufactured animal feeds are not rich in B12, livestock is often supplemented with B12 by either enriched animal feed or by intravenous injection. B12 supplementation is vegan itself as it is synthesised by bacteria, sourced from bacteria cultures, and is able to be manmade/manufactured. Because B12 is created by bacteria, it is found in foods like nutritional yeast (made from a single-celled organism grown on molasses); in fermented soy products such as tempeh; in seaweeds such as nori (purple laver), and algae like chlorella.
How to Meet your B12 Needs
Although it is not possible for one individual plant based b12 source to meet ones daily b12 need, a varied plant based consumption of the list above can provide significant amounts of b12. Sprinkle Nutritional Yeast on your food as if it was cheese, add chlorella powder to your smoothies, and/or add tempeh to your sandwich or salad. However, according to the current consensus of present evidence based research, B12 found in plant foods is incapable of supporting our required needs; thus it is not recommended to rely on them as an exclusive source. Vitamin B12 is not a vitamin of great concern for vegetarians who regularly consume eggs or dairy products (lacto-ovo-vegetarians).
The research position on B12 has changed numerous times over the past few decades, leading to many circulations and varied reports. Because proper B12 intake is vital, supplementation is recommended for vegans to ensure adequate consumption. If you are concerned about your B12 intake, I would recommend discussing with your doctor and/or dietitian. Stay tuned next week to learn about the next important mineral for plant based eaters to watch for: Zinc.
1.Trafton, Anne. MIT Biologists Solve Vitamin Puzzle. MIT News. 2007 Mar 21. http://news.mit.edu/2007/b12
Weber MF, Verhoeff J, Holzhauer M, Bartels CJ, van Wuijckhuise L, Vellema P. Vitamin B12 supplementation and milk production on farms with ‘chronic wasting’ cattle. Tijdschr Diergeneeskd. 2001 Mar 15;126(6):218-23. PMID: 11285643
Watanabe F, Yabuta Y, Bito T, Teng F. Vitamin B12-containing Plant food sources for vegetarians. Multidisciplinary Digital Publishing Institute (MDPI). Nutrients. 2014 May; 6(5): 1861-1873. Doi: 10.3390/nu6051861
Vitamine B12 (cobalamine). Voedingscentrum Encyclopedie. Accessed Oct. 14, 2017 http://www.voedingscentrum.nl/encyclopedie/vitamine-b12.aspx