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Vitamin B12 Deficiencies in Vegans

The Truth About Vegan Health and Vitamin B12 Deficiency

If eating a vegan diet is so healthy, why are there more and more vegans showing up who are skinny and appear to be malnourished and unhealthy in appearance? People choose to eat a vegan diet for a variety of reasons. Most of these reasons stem from deep convictions that should be respected by all, even if going vegan isn’t for you. 

One of the major culprits of some vegans looking and feeling unhealthy is Vitamin B12 right alongside iron deficiencies. This doesn’t have to happen to you if you educate yourself to know how to optimize your vegan diet for ultimate health.
It only stands to reason that because Vitamin B12 comes from micro-organisms that are found mostly, and almost entirely, in food borne from animals that vegans are at risk for a deficiency of Vitamin B12. Also, since vitamin B12 has a huge part to play in how iron is used by the body; vegans are at a higher risk of developing iron deficiency. How serious is this Vitamin B12 deficiency among vegans? One most recent study suggests it might affect as many as 92% of strict vegans. So, how can this be corrected without giving up your vegan lifestyle?

The Facts About Vitamin B12

Vitamin B12 is unique because it is the only vitamin that is not recognized as being reliably supplied from a combination of whole food, plant-based diet and proper sun exposure. It is found in the meat of animals, because their guts produce the microorganism. Before your stomach churns at the thought of eating meat, there are some more things you need to know about Vitamin B12.
The human gut also produces some Vitamin B12, but it is formed below the point where the body is able to absorb it back into the body for use. The good news is that since Vitamin B12 comes from bacteria, microorganisms, consuming animal foods are not necessary to obtain the necessary amounts of Vitamin B12. Though, today’s vegans will not get enough of this vital nutrient without supplementing with, of course, a non-animal based supplement.

Long ago, vegans were able to get an ample amount of vitamin B12 from fresh water and from the soil that was on the plants they consumed. Today, our water is heavily treated and chlorinated, and most of the microorganisms found in the soil are washed away or depleted to begin with.

What is Vitamin B12, Anyway?

Vitamin B12 is also called cobalamin, in part because it contains cobalt. B complex vitamins act as helpers, or cofactors, within a variety of enzyme systems within the body. A couple of these biochemical reactions include synthesis of fatty acids and DNA. In other words, Vitamin B12 helps to build the material in the body that makes up your genetic blueprint, known as DNA and is important to help with the production of red blood cells, which carry oxygen throughout the body and need to be replenished every 3 months, as well as maintaining a healthy nervous system and in releasing energy from the foods we eat. Vitamin B12 also works together with folic acid to synthesize the amino acid methionine, which limits the unhealthy amounts of homocysteine.
Vitamin B12 is often referred to as the energy vitamin. It is a water-soluble vitamin, which usually means it exits your body during urination. However, Vitamin B12 is unique. Even though it is water-soluble, it is actually stored in the liver, kidneys, and other tissue. Because of this, it can take years before a Vitamin B12 deficiency becomes apparent. Though, in that time, the damage is sometimes irreparable. That is why it is important to head it off at the pass to avoid unnecessary health issues.

Things that vitamin B12 helps with:

• Physical, mental and emotional energy
• Healthy immune system
Reproductive health and pregnancy
• Proper digestion and food absorption
• Helping the body use iron efficiently
• Carbohydrate and fat metabolism
• Healthy nervous system functions
• Promotion of normal nerve development and growth
• Forming and regulating healthy red blood cells
• Proper circulation
• Adrenal hormone production
Regulating the mood with feelings of well being
• Memory function, Mental clarity and concentration

Impostors – Don’t Be Misled

There are a few plant foods that contain Vitamin B12, but the vitamin in these plants such as spirulina, tempeh, barley grass, and nori, are actually B12 analogs. An analog is a substance that blocks the uptake of the beneficial Vitamin B12. In other words, when a vegan thinks he or she is getting enough Vitamin B12 from plants, their body is actually crying out in the need of more of the vitamin they thought they were providing. These B12 analogs (impostors) actually disrupt the B12 metabolism while masquerading as true B12. In reality, these impostor Vitamin B12 analog-rich plants intensify the body’s need for more Vitamin B12.

What are the signs of Vitamin B12 Deficiency?

• Anemia
• Nervous system damage
• Risk of heart disease
• Pregnancy complications
• Loss of energy
• Muscle Weakness
• Fatigue
• Tingling
• Numbness
• Nervousness
• Weight Loss
• Premature aging
• Gastrointestinal Issues
• Dark spots on the skin
• Lack of menstruation
• Loss of Appetite
• Dementia
• Alzheimer’s
• Reduced sensitivity to pain or pressure
• Blurred vision
• Abnormal gait
• Sore tongue
• Poor memory
• Confusion
• Hallucinations
• Vision loss
• Personality changes
• Depression
• Paranoia
• Cancer
• Hyper-Active Reflexes
• Failure to thrive in infants
• Developmental and learning disabilities in children

How Do I Know If I’m Getting Enough B12?

Testing the blood for levels of B12 in vegans often shows up false positives, because many plant foods and algae contain B12-analogs. B12-analogs are also referred to as “False B12” or “imposters” because it imitates real B12 and actually tends to interfere with B12 metabolism. Instead, to get a more realistic indication, B12 is tested by measuring the homocysteine level in the blood. A doctor will look for a blood test result to contain less than 10 umol/liter. The most reliable test looks for methymalonic acid, MMA, levels to be less than 370 nmol per liter in the blood or less than 4 microgram per microgram of creatinine.

What in the world are homocysteines?

Homocysteines are a byproduct of protein metabolism. Many vegans show adequate B12 levels but still have restricted activity of B12-related enzymes. This leads to elevated homocysteine levels, which leads to risk of heart disease and stroke along with pregnancy complications. Homocysteine levels are also changed by the presence or absence of folate. This is one reason that pregnant women, those planning on becoming pregnant, and nursing mothers are instructed to supplement with folic acid.

More things to consider

MMA and holotranscobalamin II (holo-TC). HOLOTC is an enzyme that is dependent upon Vitamin B12 to help convert MMA into succinic acid. Holotranscobalamin II (holo-TC) is composed of Vitamin B12 attached to transcobalamin, which is the part of the Vitamin B12 that is actually used by the body. If MMA levels are high, it indicates that Vitamin B12 is insufficient.

How to attain vegan health without becoming under weight

The only reliable sources of B12 for a Vegan diet are foods that have been fortified with B12 or B12 vitamin supplements. Eat Vitamin B12 fortified foods at least two or three times a day, take a supplement that provides at least 10 micrograms a day, or take a weekly B12 supplements that provide at least 2000 micrograms. The United States used to recommend that an adult vegan diet be supplemented with 2.4 micrograms of B12 a day, and this recommendation increases to 2.8 micrograms for nursing mothers. 4-7 mcg is now recommended, but this is not the amount you need to take. Rather, it is the amount your body needs to absorb each day. In order to absorb this amount, you will need to take at least 250 mcg per day. If you prefer to take a supplement less often, you can also get enough by taking a Vitamin B12 supplement at contains at least 2,500 micrograms, once a week.
B12 is absorbed into the body slowly, in small amounts. The more Vitamin B12 you take, the less often you need to supplement. The less often you take it; you will need to take more to get the required amount to absorb into your body.

There is no evidence to show that exceeding the recommended dosage will cause any harm.

Vitamin B12 is a large molecule that is difficult for the body to absorb without an accompanying protein. Get the most out of your Vitamin B12 supplement by taking one that is chewable, through an oral mist, or sublingual, to be dissolved under your tongue. Using a sublingual delivery helps the body quickly absorb the vitamin. Look for a supplement made with methylcobalamin, which is more readily used by the body because it is the natural kind of B12 that comes from bacteria. You can also get Vitamin B12 supplements in the form of a shot, at your doctor’s office, as a patch, or as a prescription.

Is it really the lack of B12 that’s the problem?

Of course, there are studies that suggest that the lack of Vitamin B12 comes from an intestinal disease, rather than a deficiency found in a vegan diet. Regardless, because it is so easy to remedy through supplementation, most experts recommend a vitamin B12 supplement. Since Vitamin B12 is considered to be safe and is available in a formula acceptable to the vegan diet, why take a chance on developing potential irreversible damage?

Let me know what health issues you have questions about, I’ll see if I can provide some insight. – Catherine


1 Like
  • Chloe

    I recently heard about a new oral prescription alternative to the injections called Eligen B12. I recently read that it works even if you don’t have intrinsic factor (so even if you don’t have normal gut absorption). Apparently it came out a month or two ago. Has anyone heard of it or tried it??

  • Helen Tam-Semmens

    This article failed to mention that 90% of B12 supplements produced are fed to farm animals. Yes, farm animals are in the same boat as we. And getting B12 second-hand through animals is VERY inefficient. That’s why non-vegans get B12 deficiencies too. Best is to take B12 supplement directly and skip the meat and dairy, and hence the health problems that come with that.

    It is not only the antibiotics and hormones and the infected meat and toxic chemical washes that cause us health problems, studies show that just animal protein itself triggering cancer-causing IGF-1 in our bodies, as well as Neu5Gc which triggers toxic immune response in our bodies every time we eat meat and dairy are also to blame.

    Shortly after I became a vegan, I found that my autoimmune disease rheumatoid arthritis, my IBS and acid reflux were all gone. I am also more energetic than ever. And I’m not an isolated case.

  • Josie M. Callicoat

    Hi Dr. Catherine.

    Thank you for sharing your expertise on this topic.

    I have a friend who is a vegan and I did notice some of the symptoms you listed above as signs of B12 deficiency – weight loss, lack of energy, and getting nervous even with little things.

    I want to help her out by suggesting healthy and safe ways for her to get additional B12 supplements. I’ve heard a vitamin therapy can be one thing, something like this:

    Your thoughts on this kind of treatment? Thanks!