What Every Vegetarian Should Know About Vitamin B12

Ask any omnivore what they think the biggest problem with vegetarian and vegan diets is, and they'll point you to either iron or protein deficiencies. While vegetarians and vegans can indeed end up deficient in either, making sure you get enough iron and protein from non-meat sources really isn't that hard. 

Not so with vitamin B12. 

Vitamin B12 is present in almost all food products of animal origin, including meat from mammals, shellfish, fish and poultry. It's also found in dairy and eggs, which may offer some consolation to vegetarians, though nearly all B12 is gone after eggs have been heated — which almost always happens before you consume them. Vitamin B12 is also present in some algae (including the spirulina that's so popular among many vegetarians and vegans), but scientists have concluded the form found in algae is mainly "pseudovitamin", as opposed to biologically active B12. What's vitamin B12 not present in? Everything else you'd eat as a vegetarian, unless it was fortified. 

Does this matter? You bet. Let's examine why.

Vitamin B12: The Basics

Vitamin B12 is a water-soluable vitamin, one of eight B vitamins. It's made by some types of bacteria, which can synthesize it. Note: because B12 is made by bacteria and bacteria are involved in the fermentation process, some people believe that fermented plant products, notably kimchi, contain B12. While we should mention that kimchi can contain fish and may be a source of vitamin B12 as such, the bacteria that make B12 aren't involved in the process of fermenting plant foods, and kimchi and similar foods should not be relied on as a source of B12. If you're veggie, you're probably making sure your kimchi doesn't have fish in any case.

Why do you need vitamin B12? It's actually involved in some pretty important stuff, including keeping your brain, nervous system, DNA, and metabolism working the way it should. Because a vitamin B12 deficiency can boost your levels of the amino acid homocysteine, an amino acid that's strongly correlated with increasing a person's risk of heart attack and stroke, a B12 deficiency puts you at risk. 

READ Vegetarian Children: Benefits And Concerns

I'll admit it: as a life-long vegeterian, a vitamin B12 deficiency had never been on my radar, until I saw my doctor about symptoms I really didn't want to have. Find out whether you have similar symptoms on the next page.

Vitamin B12: Tell-Tale Symptoms, Getting Tested, And Taking Supplements

What Symptoms Will You Have If You're Deficient In Vitamin B12?

A mild deficiency in B12 is actually unlikely to lead to symptoms. If you're at the stage where your deficiency has left you with anemia, you'll see some pretty significant but often hard-to-figure-out symptoms, which you may easily attribute to numerous other factors.

These symptoms are heavy, constant fatigue (the symptom that encouraged me to see a doctor), heart palpitations, shortness of breath, pale skin, bowel issues (both diarrhea and constipation), and a feeling of weakness and tingling in the extremities (again, I had both). A vitamin B12 deficiency can even lead to vision issues and cognitive symptoms like confusion, memory loss, and depression. You don't want those.

It's important to note that being a vegan or vegetarian isn't the only cause of a B12 defiency. Being a heavy drinker, certain immune system disorders (including lupus), atrophic gastritis, celiac disease, Crohn's disease, having had a gastric bypass for weight loss (though you'd generally be prescribed supplements automatically), parasitic infections, and pernicious anemia (which messes with your ability to absorb B12) can all do it too. A B12 deficiency isn't just a vegan/vegetarian thing.

What Should You Do If You Think You Could Be Deficient?

Go to your doctor, who will order blood tests for you. If you're a vegetarian, you may want to ask your doctor for a blood homocystine test specifically, because that pseudovitamin B12 we mentioned earlier may give a false result if you eat lots of algae. 

We should also note that vegetarians and vegans aren't necessarily deficient, since quite a few foods (including breads and non-dairy milks like almond and soy) are fortified with vitamin B12 these days. However, if you aren't already taking a supplement or making sure you regularly get B12-fortified foods, you will probably want to go for a blood test anyway, even if you don't have symptoms. A vitamin B12 deficiency adversely affects your health, and you don't need to wait until you do have symptoms before taking action.

What If You Are Indeed Deficient?

Though the recommended daily intake varies from country to country, the recommended amount in the United States is 2.4 µg (micrograms) of vitamin B12 a day. If your blood test shows that you are deficient, your doctor will tell you to take a supplement. However, it's possible to get your recommended daily intake of vitamin B12 through fortified foods as well. The nutrition labels on those foods will tell you how much B12 can be found in these products. 

READ Could Being A Vegetarian Lower Your Sperm Count?

In short, while a vitamin B12 deficiency may not have been on your radar, it's important to take this seriously. Your body will thank you. By the way, now that I have been taking supplements for a while, I feel much better. That fatigue and tingling in the extremities is gone, and I seem to be able to concentrate better than before. So, if in doubt, don't wait: get yourself checked out.