Is Vegan Vitamin B12 REALLY Necessary?

Do we really need Vegan Vitamin B12? Do you have to take it to avoid a deficiency? What are B-12 sources?

Whew! Talk about a confusing nutrient. Let me help you take the mystery of out this important topic.

"How Important Is Vitamin B-12"

For years I didn't give B-12 a second thought. I was very headstrong and believed I could get everything I need from my plant-based diet.

But you know those cute little red blood cells that are moving throughout your entire body? Well, Vitamin B-12 is required for these red blood cells to form and grow.

Red blood cells are SO important. They attach themselves to oxygen, which they carry along to your tissues. When they get to an area where the oxygen is needed, they deposit their oxygen load and pick up carbon dioxide which they carry back to the lungs.

How important are these little guys?! Very. Your red blood cells work so hard that they live for just 3 short months. So it's vital that you replenish their numbers.

Vitamin B12 also helps to build your immune system, and if you're pregnant or trying to get pregnant, your intake is extremely important.

But perhaps the most well-known reason for ensuring your intake of this nutrient is sufficient is the number of nervous, mental and emotional disorders that occur if you're not getting enough (more on this later).

"Where does Vitamin B12 come from?"

It's very important for you to grasp that in our modern food supply B12 is found MOSTLY in animal products. The bacteria in the stomach of cows (and also goats, sheep, deer, etc.) can synthesize B12, which is then absorbed by their small intestines, thereby imparting the animal with B12. So non-vegetarians get their B12 from eating these animal products.

Humans CAN AND DO make B12-synthesizing bacteria in their large intestine. The challenge lies in the fact that it's actually ABSORBED in the small intestine, which is upstream.

Fortunately, the cells of our stomach actually make something called "intrinsic factor" which seeks out B12 from food and together they make their way to the small intestine where the B12 can be absorbed. So we need this intrinsic factor because B12 is the only nutrient that requires help in order to be absorbed.

But the key take-away in the above paragraph is "B12 from food." In days gone by, B12 was plentiful because we ate foods that were not as deep cleaned and practically sanitized (!) as they are today. So the bacteria in our guts were able to synthesize the B12 we need.

Since times have changed, then, it's important that all Vegans supplement their diet with B12.

Let's see what the amazing Dr. Greger from has to say about the matter. It seems pretty straightforward to me, how about you?...

So because it's inexpensive to buy, and what is not used is flushed through, supplemental B12 is a quick and easy solution to this modern-day dilemma.

"How much Vitamin B12 do I need?"

If you eat a plant-strong diet, you MUST be sure you're getting the amount of B-12 you need.

The recommended amount of Vitamin B12 USED TO BE 2.4 micrograms per day. But after further studies, it has been raised to 4-7 mcg per day. BUT...and that's a big but (!)...that's not how much you should take daily, that's how much you need to ABSORB daily.

In order to absorb the recommended 4-7 mcg Vitamin B12 per day, you need to take at least 250 mcg daily through the use of B12 supplements and/or B12-fortified foods which contain at least 25% of the recommended RDA (which can of course be found in the Nutrition Facts on the label).

If you're the type of person who would prefer to take your Vitamin B12 supplement once per week instead of once per day, then you'll need to take at least 2,500 micrograms per week.

"But Sassy, if the recommended 250 mcg per day is multiplied by 7 days per week, that equals 1,750. So why the heck is the recommendation at least 2,500 micrograms per week? That doesn't add up!"

It's because if you take your B12 less often, you need to take MORE to get your required absorbable intake of B12.

As you can see, by giving your body a constant supply of Vitamin B12 (every day) you need far less than if you supplement once per week.

"Should I worry about a Vitamin B12 Deficiency?"

It can be hard to spot a deficiency. Why? Because enough B12 can be stored in the liver to last 3-6 years. So, for instance, if you switched to a plant-based diet 5 years ago, but haven't been paying any attention to your B12 intake to replenish those stores, you could be on your way to a harmful deficiency. And by the time you notice, it could be too late.

Also, remember when we talked about "intrinsic factor" above? Well, not everybody produces intrinsic factor! So whether you supplement or not, if their body doesn't produce intrinsic factor you can't make use of the B12 you take in. Most people simply do not know if they fall into this camp or not. There are certainly tests that can bring this to light, though, and in this case B12 shots (which bypass the digestive process altogether) may be in order. Best to ask your doctor.

So, please be conscious of your B-12 intake. A Vitamin B12 deficiency is nothing to mess around with. It can lead to anemia, constipation, weakness, loss of appetite, weight loss, depression, confusion, dementia, poor memory, soreness of the mouth or tongue, and irreversible nerve damage (such as tingling and numbness in the hands and feet), among other symptoms.

(Of course, many of these can be caused by other medical conditions, so if you have any of these challenges, be sure to speak to your physician about your concerns.)

So be smart. Give your body the Vitamin B12 it needs. It's nothing to mess around with. ;O)

What if your supplements contain more than the amount you need? It's no biggie. Since it's water soluble, what your body doesn't use is just flushed away so it's completely harmless to take more than you need.

I recommend you nab a bottle of sublingual tabs because they're easy to take.

What's the best B12 supplement for vegans? The brand doesn't necessarily matter. Whether or not to look for B12 which is made with cyanocobalamin or methylcobalamin is the bigger question...

Most experts recommend your B12 be made with cyanocobalamin, but some recommend methycobalamin. So it can be pretty confusing out there. Believe me, I understand!

The best advice I can give you is to just grab some B12 and get started. As time allows, do your research, talk with your doctor or nutritionist, and come to your best conclusion as to which form and amount of B12 is right for YOU.


"Just wanted to send you a personal thank you. I have a two year old and a five month old. B12 has been a game changer for me. I have been a very tired vegetarian for a long time, with the vitamin I feel like I got my life back. I have been 'wogging' every day during naptime on the treadmill, something I never would have done before retaking your weight loss course. With lots of love and true respect. Shanna and her babies."
-- Shanna C., Santa Clara, California

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