什么蔬菜或谷类含有维生素B12？

Read more:Vitamin B12 Benefits & Side Effects

Vitamin B12is a water-soluble nutrient synthesized by microorganisms and found naturally in a variety of foods, primarily in animal products. Foods like fish, shellfish and meat products are the types of foods that are well-known for having high levels of naturally occurring vitamin B12.

Vegan- and vegetarian-friendly vitamin B12 is less readily available than that in animal products. Vegetarian-friendly foods likeeggs and milk productsare considered good sources of vitamin B12. Vegan-friendly sources of vitamin B12 are typically fortified grains and cereals, though vegetables with vitamin B12 also exist.

Read more:List of Foods High in Vitamin B12

维生素B12和vegan or vegetarian foodsaren't usually discussed together. However,其实有各种各样的素食主义者/素食与维生素B12。These foods are often fortified, but may also be naturally occurring.

Grains and yeastsare often fortified with vitamin B12. These are the most common vegan-friendly sources of this vitamin. Although these foods and the ways they are supplemented vary between products, single servings often constitute the entirety of the recommended daily value for this vitamin.-

Cereals like wheat, maize, millet and oats contain a variety of nutrients, including protein, calcium, iron, thiamine, riboflavin and niacin. However, there isno naturally occurring vitamin B12in these foods. Despite this, many cereal products contain vitamin B12 — through fortification.

In the United States,breakfast cerealsare one of the most common sources of vitamin B12. According to theUSDA Food Composition Database,breakfast cerealscan contain as much as 9.67 micrograms of vitamin B12 for every 100 grams of food. The cereals with the highest B12 content include Honey Bunches of Oats, Malt-O-Meal, Cheerios, Golden Crisp and Fruity Pebbles.

In general,fortification of grains and cerealsis thought to be positive, as it helps people easily attain their recommended daily allowances of several nutrients. However, there is some concern thatcertain foods may be excessively fortified。This means that products across the world are often fortified in different ways. Always look at the nutrient to serving size ratio to understand the quantities of vitamins you're obtaining.

Vegetables can have vitamin B12, althoughmost plants don't need this nutrient和consequently don't produce it. This includes common vegetables like broccoli, asparagus, and mung bean sprouts and rarer items of produce, like Japanese butterbur, tassa jute and water shield. However, the levels of vitamin B12 in these vegetables are只有微量。

Certain mushrooms, like black trumpet mushrooms and golden chanterelle mushrooms, contain high naturally occurring levels of vitamin B12. These levels are approximately1.09 to 2.65 micrograms of vitamin B12每100克干蘑菇。香菇μshrooms have particularly high levels of B12, averaging 5.61 micrograms per 100 grams of mushrooms, which means that just 50 grams of these dried mushrooms could provide adults with their recommended daily allowance of vitamin B12.

Certain types of sea vegetables, like algae such asgreen laver and purple laver(the most widely consumed types of edible algae), are rich in vitamin B12. Green laver contains about 63.6 micrograms of B12 per 100 grams, while purple laver contains about 32.3 micrograms for the equivalent weight. Notably, the vitamin B12 levels in laver and other types of algae can be influenced by factors like cooking and seasoning.

Other types of algae, including red algae (like purple laver) and different species of green algae (likeChlorella, which is used in supplements), contain vitamin B12 in highly variable amounts. Red algae have anywhere from2.8到60.2微克of B12 for every 100 grams of the food. Green algae likeChlorellacan have essentially no vitamin B12 or as much as 415 micrograms of B12 per 100 grams.

Other sea vegetables also act as noteworthy sources of vitamin B12. Vegetables likesea buckthorn berries, sidea couch grass and elecampaneall have vitamin B12. Anywhere from 11 to 37 micrograms of B12 per 100 grams may exist in these plants. According to a 2018 study in theJournal of Experimental Biology and Medicine, sea vegetables like these are believed to exist symbiotically with the microorganisms that produce this nutrient.

Only microorganisms are able to produce vitamin B12, but this means that foods with microorganisms — like yogurt and fermented vegetables, like kimchi and sauerkraut, contain substantial amounts of this nutrient. Fermented foods like豆豉，纳豆，泡菜，发酵茶和泡菜all contain vitamin B12.

The vitamin B12 levels in these fermented foods can vary substantially, however. For example, tempeh contains 0.7 to 0.8 microgram per 100 grams of food, but other soy products that are fermented don't have values nearly that high. Similarly, foods like kimchi contain relatively trace amounts (about 0.1 microgram per 100 grams). However, according to both a2014 study和2016 studyin the journal Nutrients, it is possible to enrich vitamin B12 content in fermented vegetable products using lactic acid or propionic bacteria.

Many foods like these are more popular in Asian or Eastern European cultures. However, with the growing body of research regarding theimportance of the gut-brain axis, these foods are becoming increasingly popular. This may mean that fermented vitamin B12 foods may soon become more accessible and affordable in Western societies.

Vitamin B12 can be found in plants when they are grown using要么ganic fertilizers or hydroponics。几种不同的方法存在，可以增加蔬菜的营养价值。这些植物本来就在B12低。

According to a 2014 study in the journalNutrients, vitamin B12 in spinach increased substantially when these plants were grown using fertilizers such as cow manure. These methods provide an easy, affordable solution to enriching vegetables with nutrients. However, based on current methods, this vegetable alone would be insufficient to provide vegan dieters with their complete recommended daily allowance of vitamin B12.

Plants can also be grown using methods能够丰富他们的水平的维生素B12。These enriched produce items can help vegans meet their vitamin B12 recommended daily allowances, unlike plants grown using organic fertilizers. Such products are not yet easily available to the public, but may be in the near future.

You may be wondering why vitamin B12 is of so much interest and why people are continually looking for alternative ways to enrich plants with this nutrient. Vitamin B12 is critically important, as it helps keep thebody's nerve and blood cells healthy。It helps make DNA, the genetic material found within all of the body's cells.

Notably, vitamin B12 is not the same in natural and supplemented form. Vitamin B12 found in vegetables, dairy and meat products is processed differently from synthetic vitamin B12. Just over half of every microgram of natural vitamin B12 is absorbed by the body, but only about2 percent of this vitaminis absorbed when taken in supplement form.

Read more:Vitamin B12 Benefits & Side Effects

In order for the body to take up vitamin B12, hydrochloric acid in the stomach must separate B12 from the protein in food to which it's attached. Vitamin B12 then combines withintrinsic factor, a glycoproteinin the stomach, that allows for the absorption of this nutrient. Synthetic B12 doesn't need to go through the first stage of this process as it's already free and doesn't require the initial separation. Intrinsic factor and the second step are the most critical aspect related to absorbing this nutrient.

Without sufficient quantities of vitamin B12, people may experience a wide variety of issues. This includes problems with coordination, mental health or soreness of the mouth and tongue. Certain people also have issues with the production of intrinsic factor, which means that they cannot absorb vitamin B12. Issues of this type can result inpernicious anemia, or Biermer's disease。

Along with people who have trouble producing intrinsic factor, people who arevegan, vegetarian要么avoid meat productsare considered likely to be B12 deficient. B12 deficiency symptoms include issues with memory and mental health, such as confusion and depression. B12 deficiency is also known for causing problems with oral health, including aswollen, beefy tongue,burning sensations, discolorations and lesions throughout the mouth.

它比你想象的要成为B12缺乏容易。这是因为维生素是水溶性的, which means it's excreted in the urine. Consequently, people need to consume it on a daily basis.

If you believe you're vitamin B12 deficient, you should consult your doctor before starting any supplements so that youtake the right amount。If your symptoms are particularly severe, you might require very large supplements. You may also be prescribed highdoses of this vitamin是注入，而不是吞噬。

Correcting B12 deficiency is easy enough, fortunately. Supplements are readily available, and high doses of this nutrient have been临床推荐了很多年。最近的多项研究，包括在2018年的研究Cochrane Database of Systematic Reviews年和2017年的研究中American Family Physician Journal, showed that doses between 1,000 and 2,000 micrograms of vitamin B12 are a safe and effective way to treat symptoms of B12 deficiency. Such large supplements are also able to resolve complex issues, like anemia and neurological symptoms.

Despite the ease of correcting this deficiency with supplements, it's always best to try to obtain all of your nutrients naturally from the food you eat, as deficiencies may have long-term negative effects. If you're adhering to a vegan diet or avoiding animal products, try to focus on consuming fortified foods, like breakfast cereals, every morning. Alternatively, incorporate foods that contain large amounts of vitamin B12, like algae and mushrooms, into your daily meals.