Which seed is rich in B12? Exploring Plant Sources

December 31, 2025 •

4 min read

Vitamin B12 is primarily produced by specific bacteria, not by plants, which means that no seed is a natural source of this essential nutrient. This is a critical piece of information for anyone following a vegan or plant-based diet, as B12 must be obtained through alternative means.

Quick Summary

The search for a seed naturally high in B12 is a common misconception, as plants do not produce this vitamin. Reliable sources for plant-based diets include fortified foods and supplements.

Key Points

Source of B12: No seed is naturally rich in vitamin B12; the vitamin is produced by bacteria, not plants.
Common Misconception: Some lists incorrectly cite seeds like sunflower or pumpkin seeds as B12 sources, confusing them with other nutrients or fermented products.
Reliable Vegan Sources: The only dependable plant-based sources of B12 are fortified foods, such as cereals, nutritional yeast, and plant-based milks, or B12 supplements.
Fortification is Key: The B12 found in some seed-derived products, like fermented seed milk, is due to added bacteria, not the inherent properties of the seed itself.
Avoid Deficiency: Ensuring adequate B12 intake is crucial for health, as deficiency can cause serious anemia and nervous system damage.
Optimizing Absorption: For best absorption, obtaining B12 from fortified foods throughout the day or through regular supplementation is often discussed as an approach to support adequate intake.

The Truth: Seeds are Not a Natural Source of Vitamin B12

Many people mistakenly believe that certain seeds or nuts can provide a reliable source of vitamin B12, but this is a persistent myth. Unlike other B vitamins which can be found in a variety of plant foods, B12 (cobalamin) is almost exclusively derived from animal products, or created synthetically for fortified foods and supplements. The vitamin is produced by microorganisms and enters the food chain through various pathways. Therefore, if a seed product contains vitamin B12, it is due to fortification or bacterial fermentation, not a natural property of the seed itself. For example, a 2022 study showed that sunflower seed milk could be fermented using specific bacteria to produce high levels of B12, but the raw seed does not contain it.

Why the Confusion About B12 in Seeds?

Misinformation often leads to the belief that seeds contain B12. Some sources misrepresent data, confusing other B vitamins found in seeds with B12, while others incorrectly list seeds among B12-rich foods without clarifying that any content is due to fortification. Additionally, some plant-based foods, such as certain algae (like spirulina and dried nori), may contain B12-like compounds, or analogues, that are not biologically active in humans and can actually interfere with B12 metabolism. This makes them unreliable as a source of the vitamin.

Where to Find Reliable Plant-Based Vitamin B12

For those on a vegan or plant-based diet, relying on fortified foods or supplements is the only reliable way to get adequate B12. The Vegan Society provides clear guidance on this, emphasizing that this is a safe and effective strategy for optimal health.

Here are some of the most reliable sources of B12 for those on a plant-based diet:

Fortified Nutritional Yeast: A deactivated yeast product often used for a cheesy flavor, it is one of the most widely used and reliable sources of synthetic B12.
Fortified Plant Milks: Many soy, almond, and oat milks have B12 added. A single cup can provide a significant portion of the recommended daily intake.
Fortified Breakfast Cereals: Many common breakfast cereals are fortified with B vitamins, including B12, making them an easy way to get the nutrient.
B12 Supplements: For many vegans, a daily or weekly B12 supplement is the most convenient and dependable way to ensure adequate intake.

Comparing a Fortified Source to a Seed

To illustrate the difference, here is a comparison of B12 content in a fortified food versus a common seed. It’s important to remember that seeds offer many other valuable nutrients, but B12 isn't one of them naturally.


Source	Natural B12 Content	Fortified B12 Content (per serving)	Key Takeaway
Sunflower Seeds (Raw)	Negligible (bacteria-derived)	N/A	Excellent source of healthy fats and minerals, but not B12.
Fortified Cereal	None	Varies by brand, contains B12 due to fortification	A reliable and convenient dietary source of B12 due to fortification.
Nutritional Yeast	None	Often a potent source of B12 when fortified	One of the most potent plant-based sources of fortified B12.

Potential Health Risks of Vitamin B12 Deficiency

Without an adequate and reliable source of vitamin B12, deficiency can lead to serious health problems, including megaloblastic anemia and nervous system damage. Symptoms can include fatigue, memory loss, confusion, and nerve damage (tingling in hands and feet). Older adults and those with certain medical conditions may also struggle to absorb B12 and require a regular source. It is crucial for anyone on a strict vegan diet to monitor their B12 intake and status through a reliable source.

Understanding B12 Absorption and Needs

B12 absorption can be complex. The body absorbs it most efficiently in small amounts throughout the day. This is why eating fortified foods several times a day or taking a regular supplement is often more effective than infrequent, large doses. For example, the Vegan Society discusses approaches for meeting B12 needs, which may involve regular supplementation or incorporating fortified foods. This staggered intake optimizes absorption, which is particularly important as you age. Regular blood tests are also recommended to ensure levels are adequate.

Conclusion: No Natural B12 in Seeds, but Easy to Obtain Elsewhere

In summary, searching for a seed naturally rich in B12 is a fruitless endeavor, as this vitamin is not found in plants in a bioavailable form. However, a plant-based diet can still be perfectly healthy with careful planning. By incorporating fortified cereals, nutritional yeast, plant-based milks, or a B12 supplement, individuals can easily meet their dietary needs and avoid deficiency. The key is to seek out reliable, fortified sources rather than relying on natural plant foods.

For more detailed information, consult the NIH Office of Dietary Supplements Vitamin B12 Fact Sheet.

What to Look For Instead of Seeds for B12

Reliable Fortified Foods: Instead of looking to seeds, focus on common fortified foods like breakfast cereals and nutritional yeast. These products have B12 added during processing, providing a dependable source for plant-based diets.

Dependable Supplements: For consistent B12 intake, especially for those with absorption issues or strict diets, supplements offer a controlled and effective way to help meet dietary needs. Various regimens are available to help ensure needs are met.

Animal Products: For non-vegans, the most abundant natural sources of B12 remain animal products like meat, fish, eggs, and dairy. This is where the vitamin naturally accumulates through the food chain.

Regular Testing: It is advisable for anyone on a plant-based diet to have their vitamin B12 levels checked periodically. Blood homocysteine or MMA tests are more reliable indicators than simple B12 levels.

Bacterial Production: While not a home remedy, understanding that bacteria are the source of B12 clarifies why it's not found naturally in plants. This knowledge empowers consumers to seek out fortified or supplemental options with confidence.

Frequently Asked Questions

While no seed is naturally rich in vitamin B12, many seeds are excellent sources of other B vitamins. Sunflower seeds, for instance, are high in pantothenic acid (B5), and sesame seeds contain thiamine (B1) and niacin (B3).

No plant contains bioavailable vitamin B12 naturally. Claims that spirulina, nori, or other algae are reliable sources have been debunked, as they contain inactive B12 analogues that can interfere with true B12 absorption.

Vegans must obtain B12 from supplements or fortified foods. These include fortified nutritional yeast, breakfast cereals, and plant-based milks. This is a crucial step for preventing deficiency.

Yes, fortified nutritional yeast is one of the most reliable and potent sources of B12 for those on a plant-based diet. It contains a form of B12 that is easily absorbed by the body.

Yes. Older adults produce less stomach acid, which is necessary for absorbing B12 from food. It is often recommended for those over 50 to get their B12 from fortified foods or supplements.

Specific recommendations for B12 intake can vary. The Vegan Society suggests approaches that may involve consuming fortified foods regularly or taking a B12 supplement. Consulting a healthcare professional can help determine individual needs.

Historically, humans might have gotten some B12 from soil on unwashed produce. However, modern sanitation and farming practices make this an unreliable and unsafe source. Relying on fortified foods or supplements is the current standard.