Question:

What B12 Supplement Should I Take?

Answer:

I get this question all the time, so I finally decided to write up a blog post to point people to.

Cyanocobalamin

Cyanocobalamin is the most common form of B12 supplement and is the form found in fortified foods. It doesn’t occur much in nature, but it is the most stable form of vitamin B12, and the cheapest. It has been the most studied form and has consistently been shown to be effective. Unless there are extenuating circumstances, I recommend that people take cyanocobalamin as their B12 supplement.

Cyanocobalamin contains a molecule of cyanide, but the amount of cyanide in cyanocobalamin supplements is so small as to be physiologically insignificant (more info).

Some people have cyanide metabolism defects, and they should not take cyanocobalamin. If you are asking yourself right now if you might be one of those people, you can assume the chances are close to zero.

People with cyanide poisoning should not take cyanocobalamin. If you have not previously suspected that you might have cyanide poisoning, then you can assume you don’t have it.

People with chronic kidney problems should probably take a non-cyanocobalamin form of B12 (more info).

Finally, cigarette smokers might want to take a non-cyanocobalamin form of vitamin B12 as they can build up cyanide in their system. This is theoretical – I have never come across a vegan cigarette smoker who reported vitamin B12 deficiency based on taking cyanocobalamin and the Institute of Medicine has concluded that “The effect of smoking on the B12 requirement thus appears to be negligible (1).” (More info.)

Methylcobalamin & Adenosylcobalamin

Methylcobalamin is one of the two co-enzyme forms of vitamin B12, the other being adenosylcobalamin (known by many other names, including “dibencozide”). When I first got into the B12 issue, dibencozide was all the rage, now it’s methylcobalamin for some reason. The two forms have different functions in the body and both are necessary (more info).

Methylcobalamin is promoted by some alternative health practitioners and the supplement industry as superior to cyanocobalamin, primarily because it is a co-enzyme form of vitamin B12.

Based on many studies and case reports in the scientific literature in which cyanocobalamin has successfully cured vitamin B12 deficiency, it appears that the body can convert cyanocobalamin into methylcobalamin without any problem. The body also has to convert methylcobalamin or cyanocobalamin into adenosylcobalamin for B12 to carry out all of its functions. (A fourth form of vitamin B12, hydroxocobalamin, is the form typically found in animal products and B12 injections; it must also be converted into the co-enzyme forms.)

But is there any harm in taking methylcobalamin over cyanocobalamin? Probably not, but methylcobalamin is thought not to be as stable as cyanocobalamin and therefore higher doses are recommended, a minimum of 1,000 µg per day. Recommendations for cyanocobalamin are much lower (more info).

Some people with chronic fatigue report getting more relief from adenosylcobalamin than either methylcobalamin or cyanocobalamin (more info), while other people report feeling better only when taking both co-enzyme forms (adenosyl- and methyl-).

Cyanocobalamin supplements are ubiquitous, cheap, and well-studied, while methyl and adenosyl are much more of an unknown entity. Unless you have a good reason to be using them, I recommend cyanocobalamin.

Living Food Vitamin B12

Some companies claim to have a natural, living, plant, or raw source of vitamin B12. The B12 can come from seaweed or other unstated sources. Unless a label lists the source of vitamin B12 as cyanocobalamin, methylcobalamin, adenosylcobalamin, or hydroxocobalamin, I would not rely on it.

Specific Brands of Vitamin B12

I do not have recommendations regarding any specific brands of vitamin B12 supplements. As far as cyanocobalamin goes, I assume all sublingual or chewable tablets to be effective. I do not have an opinion on B12 skin patches or sprays.

As far as methylcobalamin supplements, as I stated above, I’m not as confident about them, and I have no opinion on any specific brand name.

Are B12 Supplements Vegan?

Yes. (More info.)

References

1. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: National Academy Press; 2000.

This is an article written for the Food Empowerment Project’s Food Chain newsletter Issue #11 (not yet published).

Soybeans and their products are often common ingredients in plant-based diets. Soyfoods include edamame, tofu, tempeh, soymilk, soy meats, soy ice cream, soy-based mayonnaise, miso, soy sauce, and many others. Soy is also one of the richest sources of protein in the plant kingdom. Because soy is so common, people with soy allergies sometimes wonder how they can possibly be vegan.

A true soy allergy can result in hives, itching, swelling, wheezing, and digestive upset. In very rare cases, a soy allergy can be life threatening and require immediate medical attention.

Soy allergies occur in 1 to 2 out of every 1,000 people. Soy allergies are often developed in infancy and many children grow out of the allergy as they age. In comparison to other typical food allergies, soy allergies tend to be slightly less prevalent and also less intense (on average).

If you think you might have a non-severe soy allergy, one way to test it is to stop eating soy for 3-4 weeks, and then try a small amount of soy and see what happens in the next 24 hours. If you think you have a severe soy allergy, you should not try soy without supervision by a medical doctor.

The good news is that although soy is very common in plant-based diets, it is not necessary. Many vegans have existed without soy. Other than soy, the best sources of protein are other legumes. Legumes include garbanzo beans (chick peas) which are used to make hummus and falafel, pinto beans used in most refried beans and burritos, black beans, lentils, split peas, green peas, black eyed-peas, and peanuts. Quinoa, seitan, and pistachios are also high sources of protein for vegans. If you eat a few servings of these foods each day, you should be getting plenty of protein.

And remember that in addition to soymilk, there is rice and almond milk, and in addition to soy ice cream there is rice, almond, and coconut ice-cream. Check labels as some might contain some soy. Daiya cheese, one of the most popular non-dairy cheeses that melts when heated, contains no soy. Field Roast meats also contain no soy.

References

Cordle CT. Soy protein allergy: incidence and relative severity. J Nutr. 2004 May;134(5):1213S-1219S. | link

Soy Allergy. MayoClinic.com. Accessed 12/12/2012. | link

Tyler, Steve. Estimating Prevalence Of Soy Protein Allergy. SoyConnection.com Accessed 12/11/2012. | link

People have been contacting me a lot about wheat and gluten lately. In reading many of the articles, the only thing I’ve found of much interest was this interview with Dr. Alessio Fassano, the Medical Director for The University of Maryland’s Center for Celiac Research.

Dr. Fassano says that a major protein in gluten, called gliadin, contains some protein fragments that humans cannot digest. He says we cannot digest them because we do not have an enzyme to break the bond between the amino acids glutamine and proline. These fragments don’t get digested and can end up in the blood where our system might react against them producing illness. In the case of celiac disease, our body reacts in a way that destroys the cells lining the intestines.

I had never heard that humans cannot digest the glutamine-proline bond, nor could I verify it. However, I did find this interesting article, Grains in Relation to Celiac (Coeliac) Disease, that has images showing the protein fragments that are a problem in celiac disease as well as the molecular structure of gliadin.

Some people who react negatively to wheat do not have celiac disease but instead have gluten sensitivity. The symptoms can be similar, though usually not as intense: digestive problems, inflammation, fatigue, joint pain, etc. (the interview with Dr. Fassano lists more). If you suffer from these symptoms, gluten could be a problem for you and it might be worth eating gluten-free for a while to see if it helps.

In terms of gluten being unhealthy for everyone – I remain rather skeptical. Here are a couple posts on grains that readers might find of interest. The research on wheat versus other grains and their relation to chronic illness or weight gain is currently lacking.

Paleoveganology has an interesting article up: Food For Thought.

Excerpt:

Consider the following two statements.
1) Homo sapiens are more adapted to meat-eating than other primates.
2) Meat-eating is unhealthy, at least in large amounts.

And, to be fair, so do a lot of vegans.

(Link)

Question:

Have you found women with iron absorption issues? For example, too many other minerals or not enough vitamin C? Or is absorption usually OK, and just the amount of iron the issue?

Answer:

Yes, many women have iron absorption issues. Almost all vegans get enough iron and enough vitamin C, so if they have iron issues, it’s probably from poor absorption. This is usually not a problem for men, but is for women who menstruate due to blood loss.

Someone might not be eating vitamin C at the optimal times for it to increase iron absorption – eat foods with vitamin C with whole grains, leafy greens, legumes and other high-iron foods. I often eat a small orange or two with my meals to increase iron absorption.

And you also need to remember that many people drink tea with all their meals, which inhibits absorption. Coffee does the same thing.

A study came out today discussing the fact that cooking can reduce the allergens in legumes. I added this to the list of benefits of cooking in Raw Food Vegan Diets.

No biggie, but thought some people might be interested.

Reference

Verma AK, Kumar S, Das M, Dwivedi PD. Impact of Thermal Processing on Legume
Allergens. Plant Foods Hum Nutr. 2012 Dec 7. (Abstract)   |   link

I’m a bit late in adding this info to the Prostate Cancer section of Omega-3 Fatty Acid Recommendations for Vegetarians.

There has been a question as to whether the short-chain omega-3 fatty acid, alpha-linolenic acid (ALA), might cause prostate cancer as a few early studies suggested. But from 2004 to 2010 there were three meta-analyses not finding this to be the case. The 2010 meta-analysis I just added to the site found that subjects who consumed more than 1.5 g/day of ALA had a significantly decreased risk of prostate cancer (0.95, 0.91-0.99) compared to those who ate less.

Reference

Carayol M, Grosclaude P, Delpierre C. Prospective studies of dietary alpha-linolenic acid intake and prostate cancer risk: a meta-analysis. Cancer Causes Control. 2010 Mar;21(3):347-55. Review. (Abstract)   |   Link

Wow – the post on Direct Evidence that Vegans have Lower Cancer Rates was one of my most popular ever. That could have partly been due to my asking people to share it with others – thank you to everyone who did that! And now, please unshare it. 🙁

I wrote the post on Monday evening. This morning (Wednesday) a reader, Dave, commented that after adjusting for BMI, the finding for vegans was no longer statistically significant AND that the authors had not adjusted for physical activity. I had not paid proper attention to either of these facts, partially due to not reading the charts in the study correctly.

The authors found significantly more physical activity among those who did not get cancer and also among the vegans, so it is quite odd that they did not adjust for physical activity. But since they did not, and while this study still shows vegans to have lower cancer rates, I no longer consider the study to be evidence that a vegan diet leads to lower cancer rates, which is the whole idea. I have corrected the original post to reflect this.

I sincerely apologize to everyone for doing such a poor job analyzing the study and then asking people to share it.

This post has a follow-up:

Take Three: Direct Evidence that Vegans have Lower Cancer Rates

– Jack

For decades, vegans have been saying that vegans have lower rates of cancer. Until now, there was no direct evidence for this. But last week a report from Adventist Health Study-2 was released showing vegans to have a lower cancer rate than regular meat-eaters. Unfortunately, there is not enough evidence to conclude that it is due to the diet.

There were 4,922 vegans in the study. After 4.1 years of follow-up and breaking the population into five categories (regular meat-eaters, semi-vegetarians, pesco-vegetarians, lacto-ovo vegetarians, and vegans) vegans had a 16% reduced risk of cancer when compared to regular meat-eaters (.84, .72-.99). Vegans were the only diet category to have a statistically significant lower risk of cancer.

These results were adjusted for age, race, family history of cancer, education, smoking, alcohol, age at menarche, pregnancies, breastfeeding, oral contraceptives, hormone replacement therapy, and menopause status. When the results were also adjusted for body mass index (BMI), the findings for vegans were no longer statistically significant (.86, .73 – 1.00). Additionally, the results were not adjusted for physical activity even though the authors found significantly more physical activity among those who did not get cancer and also among the vegans. Since physical activity could have affected the vegans’ BMI, you cannot rule out that it was simply more physical activity among the vegans that led to lower cancer rates and not the vegan diet.

When combining all the vegetarian categories and comparing them as a whole to the regular meat-eaters, the “vegetarians” had an 8% lower risk of cancer (.92, .85 -.99), but the “vegetarians” included some people who eat meat (the semi- and pesco-vegetarians). Using the BMI-adjusted model changed the finding a tad (.92, .85 – 1.00).

The follow-up period was only an average of 4.1 years – that’s not very long for a study on cancer. Hopefully, Adventist Health Study-2 will do some longer follow-up on cancer rates.

You can see the cancer rates of the other diet groups in Table 2 of the article Cancer, Vegetarianism, and Diet at VeganHealth.org.

This post has two follow-ups:

Follow-Up to: Direct Evidence that Vegans have Lower Cancer Rates

Take Three: Direct Evidence that Vegans have Lower Cancer Rates

Reference

Tantamango-Bartley Y, Jaceldo-Siegl K, Fan J, Fraser G. Vegetarian diets and the incidence of cancer in a low-risk population. Cancer Epidemiol Biomarkers
Prev. 2013 Feb;22(2):286-94. | link

I’ve had many questions about MSG over the years and so I have put this article together examining its safety.

Monosodium glutamate (MSG) is the salt of the amino acid, glutamic acid. The salt is the crystalline (not dissolved in water) form of glutamic acid. Salts of acids often end in “-ate.” Glutamic acid is a non-essential amino acid, which means our bodies can normally make all we need of it.

Although the name is very similar, glutamic acid should not be confused with glutamine, which is another nonessential amino acid that can become conditionally essential in trauma. Supplements of glutamine are used in injury healing and also promoted to bodybuilders.

The sodium portion of MSG is not the important component because as soon as MSG becomes dissolved in the aqueous medium of the body, the sodium molecule separates from the glutamate. Most glutamate that humans ingest is in the form of protein, which then gets broken down into free glutamate in the digestive tract. Beyreuther et al. report that Europeans ingest about 1 g of free glutamate on average (not including additives like MSG):

In addition to bound GLU [glutamate], some products like fresh fruits, vegetables and cheese contain various amounts of free GLU (unprocessed potatoes: 50–80 mg/100 g, tomatoes: 200– 300 mg/100 g, tomato products: up to 630 mg/100 g, long matured cheese like Parmesan: up to 1200 mg/100 g). Based on a mixed diet, intake of free GLU can be presently estimated to 1 g/day. (1)

Considering the above information, people are basically eating glutamate on a daily basis, and cannot realistically avoid doing so.

MSG has been thought to produce a reaction in some people who are sensitive to it. The reaction can include burning, tingling, numbness, facial pressure or tightness, chest pain, headaches, nausea, palpitations, asthma reactions, drowsiness, weakness, and allergic reactions.

In 2009, A.M. Williams and K.M. Woessner wrote a review on MSG (2). Willams and Woessner are with the Division of Allergy, Asthma, and Immunology at Scripps Clinic in San Diego, CA. Scripps is a nonprofit, community-based health care delivery network. I point this out because it would seem unlikely that they would be influenced by MSG manufacturers; additionally, neither researcher is listed as having industry ties at the Integrity in Science Database.

According to Williams and Woessner, hydrolyzed vegetable protein, hydrolyzed plant protein, hydrolyzed soy protein, and autolysed yeast extract are other sources of free glutamate. They also say that the majority (up to 95%) of dietary glutamate is used as energy by intestinal cells.

Williams and Woessner reviewed the studies looking at MSG and MSG Symptom Complex, which includes burning sensations, chest pain, headache, nausea, palpitations, drowsiness, weakness, and bronchospasms in people with asthma. They conclude:

Taken together, these studies suggest that there may be a small number of people at risk for developing symptoms consistent with the ‘Monosodium glutamate symptom complex’ when consuming large amounts of MSG on an empty stomach without accompanying food. Importantly, the overall incidence of ‘Monosodium glutamate symptom complex’ appears to be low, even in self-identified MSG-sensitive patients [emphasis added]. Furthermore, current evidence does not suggest that this entity is associated with persistent or serious effects.

Williams and Woessner review the published studies on MSG and asthma and conclude:

To summarize, the bulk of the studies examining the potential role for MSG as a trigger of attacks of bronchospasm in asthmatics have failed to demonstrate an association. To date, no DBPC [double-blinded placebo-controlled] challenge-confirmed MSG-sensitive asthmatic has been reported.

As for uticaria (skin rash) and angio-oedema (swelling beneath skin surface), they conclude (2):

In contrast to the case for MSG as a cause of asthmatic bronchospasm, there does appear to be some evidence to suggest that MSG may be a rare cause of urticaria, and possibly angio-oedema.

Regarding rhinitis (inflammation of the nasal passages), there have been case reports of three people who, upon rigorous testing, appeared to get rhinitis from MSG. Not much more than that is known (2).

A more recent Cochrane Database System Review found no evidence that people with chronic asthma can benefit from avoiding MSG in amounts up to 5 g (3).

I spent some time trying to figure out how much MSG is typically in Chinese food and in nutritional yeast (as a reader asked about), but didn’t find anything.

In conclusion, MSG is not some sort of highly synthesized chemical – it’s just an amino acid that we are ingesting regularly from plant foods and probably nothing for most people to worry about in moderate amounts. In rare cases someone might have an allergic reaction to MSG.

I have 2 other posts on MSG which can be seen in the MSG Archive.

References

1. Beyreuther K, Biesalski HK, Fernstrom JD, Grimm P, Hammes WP, Heinemann U, Kempski O, Stehle P, Steinhart H, Walker R. Consensus meeting: monosodium glutamate – an update. Eur J Clin Nutr. 2007 Mar;61(3):304-13. Review. Erratum in: Eur J Clin Nutr. 2007 Jul;61(7):928. | link

2. Williams AN, Woessner KM. Monosodium glutamate ‘allergy’: menace or myth? Clin Exp Allergy. 2009 May;39(5):640-6. Epub 2009 Apr 6. | link

3. Zhou Y, Yang M, Dong BR. Monosodium glutamate avoidance for chronic asthma in adults and children. Cochrane Database Syst Rev. 2012 Jun 13;6:CD004357. Review. | link