Is There Vitamin B12 in Mango Seed Kernels?

January 2, 2026 •

4 min read

Vitamin B12 is crucial for nerve function and red blood cell formation, yet it is almost exclusively produced by microorganisms found in animal products. While recent studies have generated significant interest in potential new plant-based sources, many people still question whether there is vitamin B12 in mango seed kernels.

Quick Summary

Studies have reported traces of B12 in mango seed kernels, but significant uncertainty surrounds these claims. This article explains why relying on mango seeds for B12 is risky, highlighting the potential for inactive analogues that block absorption and the need for reliable sources like fortified foods or supplements.

Key Points

Not a Reliable Source: Despite some reports claiming its presence, mango seed kernels are not a reliable source of vitamin B12 for humans.
Bacterial Origin: Vitamin B12 is produced by microorganisms, not plants. Any detected B12 in plants likely comes from bacterial contamination or inactive analogues.
Inactive Analogues Risk: Inactive B12 analogues found in some plant sources can hinder the body's absorption of functional B12, potentially worsening a deficiency.
Reliable Sources are Key: Proven sources of B12 include animal products, fortified foods like cereals and plant milks, and dietary supplements.
Health Risks: Relying on unconfirmed plant sources for B12 can lead to deficiency, with serious long-term health consequences like nerve damage and anemia.

Reports of Vitamin B12 in Mango Seed Kernels

Several research papers have reported finding measurable amounts of vitamin B12, also known as cobalamin, within mango seed kernels. One 2010 study published in an academic journal, for instance, indicated that mango seeds contained 0.12 mg/100g of Vitamin B12. A more recent review in 2022 reiterated that mango seed kernel is a potential source of various vitamins, including B12, based on the findings of earlier work. These findings have fueled speculation that this readily available agricultural byproduct could offer a natural, plant-based solution to B12 deficiency, particularly for vegetarian and vegan populations who are most at risk. However, scientific consensus cautions against relying on these findings without critical analysis.

The Critical Issue of Inactive Vitamin B12 Analogues

The primary reason for skepticism is the biological source of B12. Vitamin B12 is synthesized exclusively by certain bacteria and archaea, and it does not occur naturally in plants. The B12 detected in plant-based foods, including algae like spirulina and nori, is often the result of bacterial contamination or contains inactive B12 analogues. These analogues mimic active B12 but do not provide its health benefits. Worse, they can interfere with the absorption and metabolism of true B12, potentially masking a deficiency. For example, studies have shown that while some edible algae contain B12, the amount and bioavailability can be inconsistent and unreliable. Given that mango seed kernels are a plant source, any detected cobalamin is highly likely to be either an inactive analogue or the result of bacterial presence, making it an unreliable dietary source for humans.

Reliable Sources of Vitamin B12

Instead of unproven plant sources, individuals—especially those following vegan or vegetarian diets—should turn to reliable, consistent sources of bioavailable B12. The most common and proven sources include animal products, fortified foods, and dietary supplements.

List of Proven Vitamin B12 Sources

Fortified Plant Milks: Soy, almond, and oat milks are often fortified with B12. Check the nutrition label for cyanocobalamin.
Fortified Nutritional Yeast: A popular vegan food with a cheesy flavor, often fortified with high levels of B12.
Fortified Cereals: Many breakfast cereals have B12 added during the manufacturing process.
Meat, Poultry, and Fish: Animal products are natural, rich sources of B12, accumulated from bacteria in their digestive tracts.
Dairy and Eggs: Milk, cheese, and eggs provide bioavailable B12 for vegetarians.
Vitamin B12 Supplements: Oral supplements are the most reliable way for vegans to ensure adequate intake.

Comparison Table: Mango Kernel vs. Reliable B12 Sources


Feature	Mango Seed Kernels	Fortified Cereal	Vitamin B12 Supplement
B12 Presence	Reported traces in some studies; likely inactive analogues or microbial contamination.	Consistently fortified with bioavailable B12 (e.g., cyanocobalamin).	High and consistent dose of bioavailable B12.
Bioavailability	Unreliable due to potential analogues and inconsistent sourcing.	High; the body can absorb B12 added to fortified foods effectively.	High; passive diffusion allows for absorption even in large supplemental doses.
Risk of Deficiency	High; relying on this source is not recommended and can lead to nerve damage.	Low, if consumed regularly according to serving size.	Extremely low, if taken regularly as advised.
Preparation	Requires extensive processing to be consumed as flour, which may destroy some nutrients.	Ready-to-eat; no special preparation needed.	Ready-to-take in tablet, liquid, or spray form.
Primary Purpose	Repurposing waste, antioxidant properties.	Breakfast food, quick meal.	Preventing or treating B12 deficiency.

Conclusion: The Final Verdict

While the concept of extracting a vital nutrient from an agricultural byproduct like a mango seed kernel is intriguing, it is not a viable or safe source of vitamin B12. Scientific consensus confirms that plants do not produce B12, and any reports of its presence are likely related to inactive analogues or bacterial contamination, which cannot be reliably utilized by the human body. Relying on unverified sources for B12 can have serious health consequences, including anemia and neurological damage, especially for individuals on restricted diets. For consistent and proven intake, it is imperative to use animal products, B12-fortified foods, or reliable dietary supplements. This protects against deficiency and ensures the body receives the correct form of this essential vitamin. The Vegan Society provides excellent resources on understanding and obtaining adequate vitamin B12.

The Health Risks of Unreliable B12 Sources

Given the vital role of vitamin B12, relying on unreliable plant sources like mango seed kernels is a significant health risk. Deficiency symptoms can include fatigue, memory problems, and nerve damage, and these can progress slowly over years. The risk is particularly high for vegans and older adults. The presence of inactive B12 analogues can further complicate matters by binding to intrinsic factor, the protein needed for B12 absorption, thereby exacerbating the deficiency. Choosing proven sources is essential for maintaining optimal health and avoiding irreversible damage. For instance, dried nori has shown bioavailable B12, but its levels can vary widely and its reliability is still questioned by some experts. The safest and most transparent approach is to stick with fortified foods or supplements where the B12 type and amount are clearly listed.

Frequently Asked Questions

No, you should not rely on mango seed kernels for your vitamin B12 intake. The vitamin B12 reported in some studies is likely an inactive analogue or from bacterial contamination and is not a reliable, bioavailable source for humans.

Yes, for the most part. Since B12 is produced by microorganisms, plant-based foods do not naturally contain it. Reliable vegan sources must come from fortified foods like nutritional yeast, cereals, and plant milks, or from supplements.

Inactive B12 analogues are compounds found in some plant-based foods that structurally resemble vitamin B12 but are not biologically active in humans. They can interfere with the body's absorption and metabolism of true B12.

Vegans and vegetarians should get their B12 from reliable sources such as fortified foods and supplements. Options include fortified cereals, nutritional yeast, plant milks, and daily or weekly B12 tablets.

A vitamin B12 deficiency can lead to anemia, fatigue, memory loss, and nervous system damage. In severe cases, this damage can be irreversible. It is crucial to use reliable sources to prevent deficiency.

Yes, beyond the questionable B12 content, mango seed kernels have been shown to contain carbohydrates, protein, fat, and minerals like iron, potassium, and magnesium. They also possess antioxidant properties.

No, you should not be concerned about the reports, but rather be aware that they are not reliable for B12 nutrition. Focus on proven sources to meet your dietary needs rather than unconfirmed plant sources.