Mushrooms And B12: What's The Deal?

Vitamin B12 is an essential nutrient that supports many important body functions, including energy production, regulation of the nervous system, and red blood cell formation. While most sources of vitamin B12 are animal-based, there are a few plant-based sources that contain substantial amounts of the vitamin, including certain varieties of mushrooms. So, do mushrooms contain vitamin B12, and if so, which types?

Dried shiitake mushrooms contain B12

Vitamin B12 is an essential nutrient that supports many important body functions. It is naturally found in animal-derived foods, although a few plant-based foods contain substantial amounts of vitamin B12. These include dried purple laver (nori) and certain mushrooms.

Dried shiitake mushrooms contain vitamin B12. However, the amount of vitamin B12 in shiitake mushrooms varies. One source states that dried shiitake mushrooms contain about 2.4 mcg of vitamin B12 per quarter-cup serving (50 grams), which meets 100% of the daily value. Another source states that the vitamin B12 content of dried shiitake mushrooms varies between 1.3 and 12.7 mcg per 100 grams.

Shiitake mushrooms are cultivated and consumed worldwide, and their fruiting bodies are used in various vegetarian dishes. There are two types of high-grade dried shiitake fruiting bodies available in Japan: donko-type fruiting bodies with closed caps (early fruiting stage) and koushin-type fruiting bodies with open caps (late fruiting stage).

If you are considering adding dried shiitake mushrooms to your diet as a source of vitamin B12, it is important to consult with a healthcare provider to determine your vitamin B12 level and ensure that you are meeting your nutritional needs.

B12 is mostly found in animal products

Vitamin B12 is an essential water-soluble micronutrient that is naturally found in animal food products. Meat, poultry, (shell)fish, eggs, milk, and other dairy products are common sources of vitamin B12. Organ meats, such as liver and kidneys, are particularly rich in vitamin B12. For example, a 3-ounce serving of beef liver contains 70.7 micrograms of vitamin B12, which is nearly 3000% of the Daily Value (DV).

While vitamin B12 is typically found in animal products, there are a few plant-based sources that contain substantial amounts of this vitamin. Some varieties of mushrooms, such as shiitake mushrooms, contain detectable levels of vitamin B12, especially when dried. However, the vitamin B12 content in mushrooms can vary significantly, and the amount found in shiitake mushrooms is lower than that in animal products.

Dried purple laver, also known as nori, is another plant-based source of vitamin B12. It is a suitable food item for integration into various cuisines and is a rich source of nutrients, including iron and n-3 polyunsaturated fatty acids. Seaweed, an alga commonly consumed in Asian countries, is also a plant-based source of vitamin B12.

It is important to note that vitamin B12 deficiency is common worldwide, especially in populations with low consumption of animal products. This includes individuals with low socioeconomic status, ethical reasons for avoiding animal products, or specific lifestyles such as veganism. As a result, vegetarians and vegans may need to consider vitamin B12 supplements or include plant-based sources of vitamin B12 in their diets to prevent deficiency.

Vegetarians and vegans may need supplements

Vitamin B12 is an essential nutrient that supports many important body functions. It is naturally found in many food sources, most of which are animal-based, such as meat, fish, eggs, and dairy. While some plant-based sources of vitamin B12 exist, they are limited and often provide a lower vitamin B12 content than animal-based sources.

Vegetarians and vegans, in particular, need to take extra care to ensure they are consuming enough vitamin B12. This is because vitamin B12 is mainly found in animal-derived foods, and those following a vegetarian or vegan diet may be at a higher risk of vitamin B12 deficiency.

Plant-based sources of vitamin B12 include dried shiitake mushrooms, purple laver (nori), and nutritional yeast. However, the vitamin B12 content in these sources can vary significantly, and it may be challenging to consume enough through diet alone to meet the daily recommended intake. For example, while dried shiitake mushrooms contain vitamin B12, you would need to consume about 50 grams of dried shiitake mushrooms to fulfil your daily vitamin B12 needs.

Therefore, vegetarians and vegans may need to consider taking vitamin B12 supplements to ensure they are getting enough of this important nutrient. Vitamin B12 supplements are available in various forms, including capsules, injections, and tablets. It is recommended to consult with a healthcare provider to determine your vitamin B12 level and check for any possible deficiencies before starting a supplement regimen. Additionally, those following a plant-based diet can also incorporate vitamin B12-fortified foods into their meals, such as fortified plant-based milk, fortified cereals, and soy products.

Oyster mushrooms do not contain B12

B12 is an essential nutrient that supports many important body functions, including the conversion of food into usable energy. While mushrooms are a good source of vitamin B12 for those following a vegan or vegetarian diet, not all mushrooms contain this vitamin. Oyster mushrooms, for example, do not contain B12.

Oyster mushrooms (Pleurotus ostreatus) are a popular edible variety of mushrooms cultivated throughout the world for their unique flavour, aroma, and taste. They are considered a superfood due to their remarkable nutritional properties and health-promoting benefits. Oyster mushrooms are an excellent source of biological proteins, fibre, vitamins (C, B1, B3, folic acid), and minerals (potassium and phosphorus). They also contain significant amounts of linoleic and oleic acid.

However, despite their impressive nutritional profile, oyster mushrooms do not naturally contain vitamin B12. Vitamin B12 is generally low across most varieties of mushrooms and is typically absent from plant sources. While some mushrooms, such as shiitake, can produce good amounts of B12, oyster mushrooms are not one of them.

It is worth noting that oyster mushrooms are still a valuable source of other vitamins from the B complex group, with the exception of B12. This means they can provide your body with many important nutrients, even if they don't contain B12. For those seeking plant-based sources of B12, dried shiitake mushrooms are a better option, as they can provide the daily recommended amount of B12.

B12 is made in the gut of animals

Vitamin B12 is an essential nutrient that supports many important body functions. It is naturally found in many food sources, most of which are animal-based. These include meat, fish, eggs, and dairy.

B12 is not synthesized by animals or plants, but by certain bacteria and archaeon. The synthesized B12 is then transferred and accumulated in animal tissues, even in certain plant tissues via microbial interaction. Herbivorous ruminant animals, such as cattle and sheep, acquire vitamin B12 through a symbiotic relationship with bacteria in their stomachs. This is similar to how humans produce vitamin K, through a symbiosis with bacteria in the large intestine that make and excrete vitamin K, which is then absorbed.

In the same way, vegetarian animals have bacteria in their intestines that make vitamin B12 for them. The bacteria benefit from a steady supply of food and a warm home, and the B12 is then absorbed by the herbivores. This is an evolutionary adaptation that has allowed herbivores, and likely our plant-eating ancestors, to survive.

While edible plants and mushrooms rarely contain a considerable amount of vitamin B12, certain mushrooms do contain some B12 due to microbial interaction. These include shiitake mushrooms, black trumpet, and golden chanterelle.

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