Food rich in vitamin b12
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Food Rich in Vitamin B12: Sources and Bioavailability
Animal-Based Sources of Vitamin B12
Meat and Dairy Products
Vitamin B12 is predominantly found in animal-based foods, as it is synthesized exclusively by microorganisms and accumulates in animal tissues. Excellent sources of B12 include meat and dairy products, with the highest concentrations found in offal such as liver and kidney. Dairy products, while containing B12, have much lower quantities compared to meat. The bioavailability of B12 from these sources can vary, with ruminant meat showing a range of 56% to 89% absorption, depending on the type and preparation of the meat2 4.
Fish and Shellfish
Fish and shellfish are also significant sources of vitamin B12. The bioavailability from these sources is generally high, making them excellent options for meeting daily B12 requirements. The absorption rate from fish meat averages around 42%, while other seafood like shellfish also contribute substantially to dietary B12 intake4 5.
Plant-Based Sources of Vitamin B12
Seaweeds and Algae
Certain types of seaweeds, such as dried purple laver (nori), contain substantial amounts of vitamin B12. These are among the few plant-based foods that provide a significant amount of this essential nutrient. However, it is important to note that not all algae are suitable sources, as some contain pseudovitamin B12, which is inactive in humans1 4 8.
Mushrooms
Some mushrooms, particularly white button and shiitake, have been identified as containing measurable amounts of vitamin B12. These can be a valuable addition to a vegetarian diet to help meet B12 requirements1 8.
Fermented Foods
Fermented plant-based foods, such as tempeh, tofu, and certain fermented vegetables, can also be sources of vitamin B12. The fermentation process, involving specific bacteria, can enhance the B12 content in these foods, making them viable options for those on plant-based diets1 3 4.
Bioavailability and Stability of Vitamin B12
Factors Affecting Bioavailability
The bioavailability of vitamin B12 from different food sources can be influenced by several factors, including the form of B12 present and the food matrix. For instance, B12 in eggs is poorly absorbed compared to other animal products, with an absorption rate of less than 9%4. Additionally, the stability of B12 during food processing and storage can affect its availability. Cooking and thermal treatment often degrade B12, reducing its bioactivity2 5.
Fortified Foods and Supplements
For individuals at risk of B12 deficiency, such as vegetarians, vegans, and the elderly, fortified foods and supplements are recommended. Fortified breakfast cereals and B12-enriched plant-based products can help meet daily requirements. Supplements containing forms of B12 like cyanocobalamin and methylcobalamin are also effective in preventing deficiency4 9 10.
Conclusion
Vitamin B12 is an essential nutrient primarily found in animal-based foods, with meat, fish, and dairy being the most significant sources. For those on plant-based diets, certain seaweeds, mushrooms, and fermented foods can provide B12, though often in lower amounts. The bioavailability of B12 varies across different food sources and can be affected by food processing and preparation methods. Fortified foods and supplements are crucial for individuals who may not get enough B12 from their diet alone. Ensuring adequate intake of vitamin B12 is vital for maintaining overall health and preventing deficiency-related complications.
Sources and full results
Most relevant research papers on this topic
Vitamin B12 sources in non-animal foods: a systematic review
A varied diet containing non-animal B12 food sources can potentially meet daily recommendations for B12, reducing deficiency concerns for vegetarians and vegans.
Systematic ReviewVitamin B12 in meat and dairy products.
Ruminant foods, particularly offal, are excellent sources of vitamin B12, with processing and preparation affecting its concentration.
Highly CitedFermented vegetables and fruits as vitamin B12 sources: An overview
Fermented vegetables and fruits can provide the necessary daily amount of vitamin B12 for human health and maintenance, making them a feasible alternative for plant-based diets.
Vitamin B12 Sources and Bioavailability
Vitamin B12 bioavailability decreases with increasing intake, making animal foods, meat, milk, egg, fish, and shellfish the main sources.
Highly CitedBiologically active vitamin B12 compounds in foods for preventing deficiency among vegetarians and elderly subjects.
Identifying plant-source foods with high bioactive vitamin B12 levels and preparing crystalline vitamin B12-fortified foods can help prevent deficiency in high-risk populations like vegetarians and elderly individuals.
Highly CitedVitamin B12 Intake From Animal Foods, Biomarkers, and Health Aspects
A diet high in plant-based foods and low in animal products increases the risk of vitamin B12 deficiency, especially in populations with low consumption of animal products.
Highly CitedVitamin B12 levels in children and adolescents on plant-based diets: a systematic review and meta-analysis.
Children and adolescents on plant-based diets, especially vegan and macrobiotic diets, may be at risk of developing vitamin B12 deficiency.
Meta-AnalysisVitamin B12-Containing Plant Food Sources for Vegetarians
Dried purple laver (nori) is the most suitable Vitamin B12 source for vegetarians, providing iron and n-3 polyunsaturated fatty acids, while also providing other nutrients.
Very Rigorous JournalHighly CitedVitamin B12 sources and microbial interaction
Human vitamin B12 deficiency is mainly acquired from ruminants and fish (or shellfish) through microbial interaction, with ruminants acquiring it through a symbiotic relationship with bacteria in their stomachs.
Literature ReviewHighly CitedVitamin B12 in Foods, Food Supplements, and Medicines—A Review of Its Role and Properties with a Focus on Its Stability
Vitamin B12 stability in foods, supplements, and medicines depends on environmental factors, manufacturing process, and storage, with stabilization approaches ranging from minimal destabilization to innovative technological processes.
Literature Review