Have you decided to follow a vegan diet? Do you prefer to stay away from milk, eggs, meat, and fish? This is the guide for you. Vitamin B12 is an essential nutrient for human wellbeing, and is found in animal products. When we don't consume the required amounts, we put ourselves at risk for a wide range of diseases.
If you're vegan, vegetarian, or avoid eating animal products for any other reason, we suggest you give this article a close look. We'll be discussing the importance of vitamin B12, what to eat to prevent B12 deficiency, and how to include vitamin-fortified vegan foods or supplements if you don't consume this nutrient naturally. Are you ready to learn?
- 1 Weekly newsletter with the best personal finance tips
- 2 Key Facts
- 3 Vitamin B12 Supplements: Our Selection
- 4 Buyer's Guide to Vitamin B12: What You Need to Know
- 5 Vegans and Vitamin B12: Our Advice
- 6 Summary
- Vitamin B12 is found near exclusively in animal products (meat, fish, eggs, and dairy).
- Those of us who don't eat animal products must rely on foods fortified with added vitamin B12, or on supplements. Some people may suffer from B12 deficiency even if they have an omnivorous diet: older adults, people with chronic illnesses, or people on certain medications.
- Those who prefer to follow a vegan diet can tend to their B12 levels with fortified foods. It's also important to evaluate whether you need to take supplements, and to avoid common myths and "fake news" about this vitamin. Medical oversight is essential for vegan children, pregnant women, and elderly adults.
Vitamin B12 Supplements: Our Selection
Some people's bodies are incapable of making full use of the vitamin B12 in food. This situation can affect both omnivores and vegans who eat food artificially fortified with B12. If you've been advised to complement your diet with a vitamin B12 supplement, why don't you give one of these curated products a try?
Buyer's Guide to Vitamin B12: What You Need to Know
Vitamin B12 is a nutrient found near exclusively in the animal products we eat. Algae, fungi, and other products like tempeh (fermented soybeans) have not been shown to provide this vitamin. As such, vegans must rely on vitamin-fortified food, or vitamin supplements, if we don't want to deal with hypovitaminosis.
Why Is It Important to Include B12 Foods in My Diet?
Our own bodies cannot synthesize vitamin B12, so it must be obtained from the food we eat. Luckily, cobalamin has some of the lowest required dietary intake of any nutrient. Its daily reference intake for adults is 2 micrograms (ɥg). In other words, only 0.002 milligrams (2)!
What Are the Risks of Not Eating Foods with B12?
- Anemia. When your cobalamin reserves run out, you won't be able to create new red blood cells (the cells in charge of transporting oxygen). The red blood cells which remain end up large and deformed. In other words, the result is megaloblastic anemia ("mega" meaning large and "blastic" meaning the cell is immature). Symptoms include fatigue, unhealthily pale skin, and in severe cases, jaundice (yellowed skin).
- Dementia. Vitamin B12 deficiency may affect your myelin, a substance which covers nerves and allows your brain to transmit signals to the rest of the body. The consequence of low vitamin B12, therefore, may be loss of sensation, balance problems, and in severe cases, dementia.
- Heart Disease. Some studies have found a relationship between insufficient vitamin B12 levels and the development of cardiovascular problems and heart disease. These results, however, require validation by further study.
- Problem Pregnancies. Vitamin B12, like folic acid, is an extremely critical nutrient for the health of a growing fetus. B12 deficiency could increase the risk of birth defects and disabilities like spina bifida (defects in spinal column and spinal cord formation).
Some experts are concerned by the possibility that suboptimal B12 levels could also lead to "overall weakened" health. In other words, low B12 reserves could affect your health overall and increase your odds of eyesight problems, weakened memory, and even osteoporosis. This problem would primarily affect older people (8).
Could I Develop B12 Deficiency Even If I Include It in My Diet?
- Older Adults: The passage of time may make your digestive tract start to have trouble digesting food. This can interfere in your body's ability to absorb vitamin B12.
- Digestive Tract Conditions: People with Crohn's disease or ulcerative colitis, people who have undergone surgery which removed part of their digestive tract, and people with serious bacterial or parasitic infections can all have problems absorbing this vitamin.
- Pernicious Anemia: To be absorbed by the body, vitamin B12 must link up with a gastric receptor called "intrinsic factor". Your body can misidentify that receptor as foreign and destroy it if you suffer from pernicious anemia, an autoimmune disease. As a consequence, cobalamin deficiency ensues (9).
- People on Medications: Some pharmaceutical drugs can interfere with vitamin B12 absorption. Metformin, for example, is a very popular anti-diabetic drug used to control blood sugar. It's been linked to possible cobalamin deficiency (10). Antibiotics, HIV treatments, and methotrexate could also lead to low B12.
- Other Conditions: Thyroid problems and heart disease, among other conditions, have been linked to insufficient vitamin B12 levels.
If you're an older adult or have health problems, have no fear! Make an appointment with your doctor to discuss the need for an analysis, which will check if your B12 levels are below normal range.
Vegans and Vitamin B12: Our Advice
Those of us who follow the "compassionate diet" - vegans - may be at risk for a B12 deficiency. Vegetarians can also have low levels of this nutrient if they limit their consumption of milk and eggs (11). If that applies to you, there's no need to panic! The advice in this guide will help you prevent B12 deficiency in your plant-based diet.
- Eat Fortified Food
- Evaluate the Need to Take Supplements
- Watch Out for False Promises
- Protect Vulnerable People
Eat Fortified Food
If you've struck animal products from your diet, your B12 reserves stop replenishing themselves. After about three years (it may be earlier or later, depending on your starting levels of cobalamin), you could begin to suffer from B12 deficiency's dangerous consequences (12). You can, however, prevent that unpleasant outcome by watching your diet.
Some foods, like plant-based "milks", juice, and cereal, are fortified with added B12. They can help you ingest the cobalamin you need to stay healthy. Thankfully, the B12 in these products is cyanocobalamin, which is derived synthetically (13). As such, you can safely consider these foods cruelty-free.
Evaluate the Need to Take Supplements
Some studies call into question the actual effectiveness of fortified food. In these scientific articles, experts mistrust these products because they don't allow you to know the exact amount of vitamin B12 you're ingesting. Plus, if you're older or you have chronic health conditions, the cyanocobalamin in these foods may not end up being absorbed (14).
We suggest that, on top of eating fortified food, you ask your doctor whether you need to add a vitamin B12 supplement to your diet. If you have problems absorbing it, your doctor will prescribe "megadoses" of B12 taken orally or as injections. If you absorb it normally, your doctor may suggest you follow a supplement guideline like these (15):
- At least 10 micrograms of B12 taken once a day
- 2,000 micrograms de B12 taken once a week
Watch Out for False Promises
You may have heard certain myths and rumors about vitamin B12. For example, someone may have explained that you can get enough cobalamin by eating organic vegetables grown without pesticide, or even vegetables with a healthy bit of dirt! What truth is there to this kind of claim?
- Are the bacteria on unwashed vegetables able to produce vitamin B12? Sadly, the bacteria on unwashed food produce only minimal amounts of cyanocobalamin. The chances of indigestion or an infection, however? Substantially higher. We don't suggest you try this "natural" method (16).
- Does a raw vegan diet (not cooking vegetables) provide B12? Vegetables have not been shown to provide more cobalamin when eaten raw. Remember that this vitamin is found in animal products, not in plants (16).
- Are spirulina and other algae (like nori and chlorella) high in B12? Algae contain a variety of cobalamin which is not very useful for human bodies. Their "pseudo-vitamin B12" has very low bioavailability, meaning our bodies have very little ability to absorb and activate it. As such, it is not considered a useful way to meet required B12 intake (17, 18).
- Do buckwheat, shiitake mushrooms, tempeh, and tofu contain B12? Presently, no one has been able to show that these foods contain vitamin B12 in their natural state. They can, however, provide this nutrient if they've been fortified with added cyanocobalamin (15).
Protect Vulnerable People
Vitamin B12 deficiency can have especially serious health consequences for children, pregnant women, and older adults. Little ones can develop serious neurological problems as a result of this deficiency. Future mothers may put their pregnancy at risk, and aging adults could suffer dementia or eyesight problems (19, 20, 21).
Contact a doctor or nutritionist before putting your children on a vegan diet. Vegan pregnant women should work with a specialist who can provide the necessary information and supplements. Older people should also ask a doctor what steps to follow if they opt for a cruelty-free diet.
Vitamin B12 is an essential nutrient to keep your body in good shape. Your brain and red blood cells thank you when you include this molecule in your diet. Unfortunately, because it is found exclusively in animal products, vegans may eventually develop B12 deficiency.
Those of us who follow plant-based diets can introduce food fortified with artificial forms of B12. However, some experts recommend being much more thorough. Taking regular vitamin supplements and checking in with your doctor periodically may be a safer option for at-risk groups. What about you? Do you include B12 in your diet, or do you instead rely on supplements?
If this guide helped you discover more about vitamin B12 and your diet, feel free to leave a comment and share this article.
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