The majority of negative attention directed towards vegan diets can be attributed to its association to vitamin B12 deficiency. This vitamin, vital for many bodily functions, has long been associated with animal-based foods.
For this reason, it is often questioned how even a balanced vegan diet can supply enough B12 to meet the recommended requirement. However, a B12 deficiency can be prevented while adhering to a plant-based diet.

Vitamin B12, often simply referred to as B12 or cobalamin, is a nutrient that plays an essential role in our bodies’ overall health and functioning.
Vitamin B12 (cobalamin) is needed for several important functions in the body. Here is a list of its key functions:
These functions highlight the need for vitamin B12 plays in maintaining overall health and well-being. A deficiency in B12 can lead to a range of health issues.
Therefore, it’s important to ensure an adequate intake through diet or supplements, especially for individuals following vegan or vegetarian diet.

Yes, of course. While vitamin B12 is primarily found in animal-based foods, vegan sources of B12 exist. However, they are typically limited.
There are differences between B12 from animal products and B12 from vegan sources. The key distinctions are the following:
Yes, there are many fortified products that are vegan, as well as good sources of B12.
The best way for a vegan to get an adequate supply of vitamin B12 is through a combination of fortified foods and supplements. Here’s a recommended approach:
Vitamin B12 can present a unique challenge for vegans, since it is exclusively found in animal-based foods.
For this reason, it is important for vegans and vegetarians to be aware of their B12 intake and consider supplementation if not regularly consuming vegan sources of B12.
However, one study on plant food sources of B12 found that dried green laver (specifically called, Enteromorpha sp.) and purple lave (specifically called, Porphyra sp.) contain significant amounts of Vitamin B12, with approximately 63.6 μg/100 g dry weight and 32.3 μg/100 g dry weight, respectively.
Additionally, for those wondering about chlorella and spirulina, it is advised to check the nutrition labels for these products in search of B12 content. However, these algae supplements often contain a pseudovitamin of B12 that is inactive in humans.

There are no natural sources of vegan B12 that would be enough to meet your daily needs.
Vitamin B12 is almost exclusively found in animal-based foods.
There are very few natural plant-based sources of this vitamin. However, some natural sources of B12 do exist.
It’s essential for vegans to be aware that these natural sources of B12 may not provide sufficient intake to prevent deficiency-related health issues. Moreover, the content and bioavailability of B12 may not always be reliable or consistent.
For this reason, vegans are typically advised to rely on fortified foods or supplements to meet their B12 needs reliably.
Regular monitoring of B12 levels through blood tests is essential for vegans to verify that they are maintaining sufficient B12 status. Consulting with a healthcare provider or vegan registered dietitian can provide personalized guidance on B12 intake for vegans.
Yes, shiitake mushrooms and algae are considered plant sources of B12.
Vegan sources of food high in B12 include: B12-fortified foods, nutritional yeast, tempeh, shiitake mushrooms and algae or seaweed.
| Vegan B12 Sources | Food Item | Portion | B12 Content (mcg) |
| B12-fortified foods | Soy milk | 1 cup (250 ml) | 1.0 mcg |
| Almond milk | 1 cup (250 ml) | 1.0 mcg | |
| Oat milk | 1 cup (250 ml) | 1.0 mcg | |
| Nutritional yeast | Fortified nutritional yeast, Large flakes | 16g, 30 mL (2 heaping tbsp.) | 8.0 mcg |
| Tempeh | Fortified tempeh, Fresh weight | 100 g | 0.97 mcg |
| Shiitake mushrooms | Dry weighed shiitake mushroom | 100g | 5.61 mcg |
| Algae or Seaweed | Dried green laver (Enteromorpha specie) | 100 g | 63.6 mcg |
| Purple laver (Porphyra specie) | 100 g | 32.3 mcg |

If vegans don’t get enough vitamin B12 in their diet, they may eventually have B12 deficiency. Some people might run low on this vitamin in a few months, while it could take years for others. How bad it gets depends on how soon it’s found and fixed.
That being said, there are several factors contribute to the risk of B12 deficiency among vegans:
Given these factors, it’s crucial for vegans to take steps to prevent B12 deficiencies, such as regular monitoring of B12 levels through blood tests and consulting with plant-based registered dietitians for personalized guidance on B12 intake.
A vegan diet that lacks adequate vitamin B12 can lead to various health risks and potential complications. Here are some of the health risks associated with a vegan diet that lacks B12:
Vitamin B12 deficiency can manifest through a variety of signs and symptoms, and they can vary in severity. Some common signs and symptoms of B12 deficiency include:
It’s important to note that not everyone with a B12 deficiency will experience all of these symptoms, and the severity can vary. Additionally, some of these symptoms can overlap with other health conditions, making diagnosis challenging without proper testing.
If you suspect you have a B12 deficiency or experience several of these symptoms, it’s crucial to seek medical advice and undergo blood tests to measure your B12 levels.
Early detection and treatment of B12 deficiency are essential to prevent potential complications and health risks. A healthcare provider can determine the underlying cause of the deficiency and recommend appropriate treatment, which may include B12 supplementation or dietary changes.

There are 3 ways you can increase your B12 levels:
The best way to raise B12 levels fast in case of a deficiency is to take B12 supplements. Moreover, for severe deficiencies, there are also B12 injections that can be offered by your doctor for rapid improvement of B12 levels.
In addition to B12 supplements or injections, increasing the dietary intake of vegan sources high in B12 is also a good way to raise B12 levels. This includes: B12-fortified foods, nutritional yeast, tempeh, shiitake mushroom, and certain algae.
Vegan sources high in B12, that are also natural, are limited. Therefore, a good answer for this question depends on whether or not B12 deficiency is present.
Without a B12 deficiency: Include natural foods high in B12 in your diet. Hence, incorporate shiitake mushrooms and the right algae or seaweed into your diet.
With a B12 deficiency: Increasing B12 levels with natural foods alone may not be the best option in the case of a deficiency. While natural foods can contribute to B12 intake, relying solely on these dietary sources may not provide the rapid and consistent increase in B12 levels needed to address a deficiency effectively.
If you suspect or have been diagnosed with a B12 deficiency, consult a healthcare provider or registered dietitian. They can provide personalized guidance on the most appropriate approach to address your specific situation.
There are certain substances that can interfere with the absorption of B12. Here are some examples of substances that could reduce or block B12 absorption:

The Dietary Reference Intake (DRI) for B12 is of 2.4 mcg per day for adults.
Yes, of course! It is possible to get enough vitamin B12 on a vegan diet alone. However, this typically requires conscious effort and attention to dietary choices.
Why? Because vitamin B12 is primarily found in animal-based foods, and natural or vegan sources of B12 are limited.
For more information on the process and fees of consulting with a plant-based registered dietitians.
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