Vitamin B12 is an important vitamin that everyone needs to live healthily. B12 plays an important role in the production of red blood cells and DNA and it’s necessary to keep your nervous system functioning properly. Therefore it’s important to prevent a B12 deficiency.
Often by the time people find out they have a B12 deficiency, they have already suffered permanent damage because of it. The symptoms of this deficiency are tiredness, a burning or deaf feeling in the limbs and difficulty concentrating and remembering things. Because these symptoms also occur with a lot of other diseases and don’t always seems very serious at first, it can take a long time before a B12 deficiency is discovered and diagnosed. If you suspect you may have a B12 deficiency, it’s best to have your blood tested. Generally B12 levels between 100 and 300 pmol/L are considered to be really low and there’s a good chance you already have B12 deficiency symptoms at this point. Lower than 100 pmol/L is a critically low B12 level and people who have this often need B12 injections for a while to overcome their deficiency.
Luckily the human body stores B12 in the liver which means that even if you don’t consume any B12 for a while or even a few years, you’ll likely still have enough of it. It’s still good to make sure you consume enough, though, to prevent getting a deficiency in the future. As B12 is the only nutrient that vegans need to supplement, it’s good for vegans to pay extra attention to adding this to their diet.
Sources of B12
It’s often said that B12 can only be found in animal products such as meat and dairy. That’s why many people say veganism is unnatural as you ‘need meat to get B12’ and your body can’t do without B12. However, while vegans definitely need to take B12 supplements, the story is more complicated than that and it doesn’t really have much to do with veganism.
B12 is made by bacteria that live in water, on plants and in our and animals’ intestines. Unfortunately B12 is made at the very end of our intestines which means it can’t be absorbed by the body anymore and leaves the body with our faeces. So it’s necessary for humans and other animals to consume enough B12. This can be done by drinking water that hasn’t been purified or unwashed fruit and vegetables. This used to be the most important source of B12 for most people throughout history, as many people were too poor to regularly consume animal products. In addition, this is also how vegans in the past (such as Buddhist monks) have managed to live perfectly healthily without B12 supplements. Unfortunately, because of our hygienic lifestyle (partly necessary because of all the pollution we cause), nowadays there’s no B12 anymore in our drinking water and we usually wash the B12 off most of our plant-based food.
Some people may think eating meat is the solution, but that’s also no guarantee for enough B12. As most farm animals today get clean water and feed, they also often lack sufficient B12 and thus often get B12 supplements. Why eat secondhand supplements when you can also just take the exact same in a supplement yourself? In addition, several studies have shown that in the US 20 to 40 percent of meat eaters have a B12 deficiency. B12 deficiency is also one of the most common nutrient deficiency among meat eaters and vegetarians. In some cases this is due to the body not absorbing B12 as well as it should. However, as both meat eaters and vegans nowadays live an unnaturally clean and hygienic lifestyle, it shouldn’t be surprising that B12 deficiency is quite common. Therefore, using B12 supplements is useful, even if you’re not a vegan.
Some websites claim that there are also plant-based sources of B12, such a seaweed or certain types of berries. However, there’s no scientific evidence showing that these plant-based sources contain B12 that can be absorbed by humans, so it’s unwise to rely on those for your B12. Often B12 is also added to plant-based milk and meat replacements. Unfortunately human bodies do not absorb B12 very well, so you need to consume much more B12 than the RDA in order to absorb the RDA. It is not possible to absorb enough B12 from just plant-based milks and meat replacements, even if you consume them every day, so supplements are still necessary.
Unless you only drink unpurified water from rivers and don’t wash your vegetables (and we advise you not to do that), as a vegan it’s necessary to take B12 supplements. Luckily most of these supplements are vegan. Make sure you get the cyanocobalamin version, as other versions of absorbable B12 such as methylcobalamin, hydroxocobalamin and adenosylcobalamin are less stable forms of B12. Therefore you need much more of these to get enough B12, so we advise you consume the cyanocobalamin version.
It’s advised that vegans take a supplement of 100 µg every day or one of 1000 µg two or three times a week. Even when you’re not a vegan, it might be a good idea to take a B12 supplement once in a while to prevent a deficiency. So far, research has shown that taking too much B12 does not cause any harm, so it’s better to consume a bit too much than to risk causing permanent damage to your body.
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Stichting B12 tekort