What food has b12
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Vitamin B12 Food Sources: An Overview
Animal-Based Foods Rich in 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, particularly those from ruminant animals like cattle and sheep. Offal, such as liver and kidney, contains the highest concentrations of B12, while dairy products have lower quantities. The bioavailability of B12 from these sources is generally high, with absorption rates varying from 42% in fish meat to up to 89% in sheep meat. However, the vitamin content can be reduced by food processing and thermal treatment.
Fish and Shellfish
Fish and shellfish are also significant sources of vitamin B12. The bioavailability of B12 from these sources is comparable to that from meat, making them excellent alternatives for those who prefer seafood. However, certain shellfish may contain inactive forms of B12, known as pseudovitamin B12, which are not useful for human health.
Eggs
Eggs contain vitamin B12, but the absorption rate is relatively low, less than 9% compared to other animal products. Despite this, they still contribute to the overall intake of B12, especially in diets that include a variety of animal-based foods.
Plant-Based and Fermented Foods
Seaweeds and Algae
Certain types of seaweeds, such as dried purple laver (nori), contain substantial amounts of vitamin B12 and are considered suitable sources for vegetarians. However, most edible blue-green algae (cyanobacteria) contain pseudovitamin B12, which is inactive in humans . Therefore, not all algae are reliable sources of this essential nutrient.
Mushrooms
Some mushrooms, like white button and shiitake, have been found to contain vitamin B12. The content varies, but they can contribute to the daily intake of B12, especially in vegetarian diets.
Fermented Foods
Fermented foods, including certain soy products like tempeh and fermented vegetables, can be enriched with vitamin B12 through microbial activity. These foods offer a viable alternative for those on plant-based diets, as the fermentation process can increase the B12 content significantly . For instance, soy yogurt and fermented soymilk have been shown to prevent B12 deficiency in experimental models.
Fortified Foods
Breakfast Cereals and Other Fortified Products
Fortified breakfast cereals are a valuable source of vitamin B12, particularly for vegans and the elderly. These products are often enriched with crystalline B12, which has high bioavailability and can help meet daily nutritional requirements.
Conclusion
Vitamin B12 is essential for human health, and its primary sources are animal-based foods such as meat, dairy, fish, and shellfish. For those following plant-based diets, certain seaweeds, mushrooms, and fermented foods can provide B12, although the bioavailability and activity of the vitamin can vary. Fortified foods also offer a reliable source of B12, ensuring that even those who avoid animal products can meet their nutritional needs.
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