What Is Vitamin B12
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B12 is a vitamin produced by bacteria in the soil and water. Prior to modern times, our ancestors consumed enough B12 from vegetation since they didn’t have the same hygienic practices of washing it before eating (or chlorinating the water to kill bacteria) like we do now.
Animals get their B12 in the same manner—they eat the grass and vegetation that has a bit of soil on it containing B12. However, it’s important to note that livestock are typically supplemented B12 because pesticides often kill the bacteria that produce B12 in soil and antibiotic use kills the bacteria in the guts of farm animals.
Why Do We Need It
B12 is essential since all cells in the body need it. The first effects of it are seen in the blood and nervous system. Megaloblastic anemia, characterized by large red blood cells, is a common result of deficiency. A patient even with severe deficiency can tolerate the low red blood cell count.
It’s often treated by supplementing. You only need 4-7 micrograms a day but your chances of getting anemia from being deficient is less than one in a million.
Additionally, it has been observed that B12 can be recycled by the body for up to 2-5 years (assuming you don’t consume any more during that time). Though it is very unlikely that you’d be able to completely avoid it for that long. So many foods these days are fortified with it.
However, there are recommendations that if you’re on a whole food plant-based diet that you should be supplementing it after three years. This is because even an omnivore can be deficient in B12. If you start off deficient when switching to a vegan diet a supplement can immediately correct this deficiency.
It’s best to get your blood tested first, and then decide whether supplementation is necessary. Most of the time though the deficiency is related to intestinal diseases and not the diet.
Best Vegan B12 Sources
It may come as a surprise that not all B12 supplements are vegan due to some animal-derived fillers, even though B12 itself is always vegan.
As previously mentioned, we need 4-7 micrograms a day of B12. If you are relying on fortified foods to acquire your vitamin B12, pay careful attention to servings sizes. If one serving only has 1 microgram of B12 in it, then you will need to consume 3 servings throughout the day to reach your recommended dietary allowance (RDA).
B12 supplements on the other hand may be more convenient and more economical. Although most supplements tend to have more of the vitamin than the body requires or can use, there is no harm in exceeding the recommended amount for this vitamin by combining sources. So no need to worry about taking a supplement and consuming a fortified food in the same day. Only intakes above 5000 micrograms per week should be avoided due to lack of evidence for toxicity from higher amounts. Better to err on the side of caution.
It is also more beneficial to chew the tablet since it increases absorption. Absorption of B12 can vary widely from about 50% if 1 microgram is consumed to about 0.5% for amounts above 1000 micrograms. Therefore, if you are consuming B12 less frequently, you need to be consuming in a higher amount. You can take a daily supplement of 10 micrograms or a weekly supplement of 2000 micrograms. The amount and frequency is up to you for what works best with your schedule.
It is also worth mentioning that individuals 50 years or older should supplement regardless of their diet. According to The Institute of Medicine, “Because 10 to 30 percent of older people may be unable to absorb naturally occurring vitamin B12, it is advisable for those older than 50 years to meet their RDA mainly by consuming foods fortified with vitamin B12 or a vitamin B12-containing supplement.”
When no dietary supply occurs, deficiency symptoms can take five years or more to develop in adults, however some can experience symptoms within a year. Even though the onset of symptoms from deficiency can take years to develop due to the body’s ability to recycle this vitamin, it is critical that you still get the recommended amount either daily or weekly depending on your choice of consumption. This is because there is no consistent pattern of symptoms and (mostly in rare cases) the damage to the nervous system can be irreversible.
Where can you get B12 on a vegan diet?
Here are my recommended sources below (this is not an exhaustive list):
- Fortified plant-based milks
- Fortified cereals
- Nutritional yeast
Be careful with nutritional yeast though as B12 is light sensitive so getting it from a bulk bin may not be sufficient. And be sure that it is fortified as not all nutritional yeasts contain B12.
The same is true for plant-based milks—double check that it is fortified as several are not. We recently picked up some almond milk from the brand Simple Truth which is fortified but we’ve had the Silk brand in the past which was not.
Best Vegan B12 Supplements
And here are some safe vegan B12 supplements that I found:
There are more than just these six I mention so just be careful that they are vegan and provide the right amount for the frequency you choose to take.