Archive for the ‘Supplements’ Category

Zinc Supplements and Cadmium Contamination

Friday, July 26th, 2013

After posting the article Cadmium Levels in Vegans, Zinc Supplements and Alzheimer’s Disease, Ginny Messina let me know that there is a concern about cadmium contamination of zinc supplements.

I researched the issue and added the following section to VeganHealth.org’s article Cadmium:

In 2001, Krone et al tested six zinc supplements from Seattle area health food stores to see if they contained cadmium (1). According to the authors, “Because the chemical properties of [zinc] and cadmium (Cd) are so similar, these two elements invariably occur together in nature.”

They found that the single zinc supplements had very low levels of cadmium whereas the multi-mineral supplements had enough that taking the RDA of zinc would provide up to 2 µg of cadmium (20% of the daily limit recommended by the US Federal Drug Administration (FDA)). It also happens that three of the supplements with low levels of cadmium were in the form of zinc gluconate whereas none of the multi-mineral preparations were the gluconate form. So, it could be that zinc gluconate is unlikely to have much cadmium or that single zinc supplements are unlikely.

According to their website, the supplement manufacturer Kirkman, from Oregon, does a rigorous job testing their supplements for contamination of cadmium and other impurities (more info). They also have an article on their site, Cadmium: A Serious Heavy Metal and Topic. They ship outside the United States.

Support JackNorrisRd.com

Please share and/or like my posts! Thanks!

I greatly appreciate donations of any amount and it allows me to spend more time on nutrition (click here).

Amazon.com Gift Cards – E-mail Delivery

Vegan for Life: Everything You Need to Know to Be Healthy and Fit on a Plant-Based Diet from Amazon.com

References

1. Krone CA, Wyse EJ, Ely JT. Cadmium in zinc-containing mineral supplements. Int J Food Sci Nutr. 2001 Jul;52(4):379-82. | link

Calcium Supplements and Cardiovascular Disease in the News

Monday, March 4th, 2013

In 2010, I wrote about a meta-analysis on calcium supplements and cardiovascular disease, Calcium Supplements: Are They Safe? The association with heart disease was limited to people who started out with a dietary calcium intake of 700 mg/day or more (not including the supplements). Then in 2011, I noted a study on supplement use in older women that found a link between calcium supplements and a lower risk of mortality (Supplement Safety).

Since I recommend that vegans get their calcium levels up to at least 700 mg and preferably the DRI (1,000 mg for adults under 50; 1,200 mg for adults over 50) by whatever means necessary (greens, fortified foods, or supplements), I try to keep track of this research as closely as I can. In February, results from two different studies looking at calcium supplements and cardiovascular disease were reported.

One study was from the USA and followed people aged 50 to 71 at baseline for 12 years (1). No association between cardiovascular disease deaths and calcium intake was found for women. For men, calcium supplements of 400 to 1,000 mg/day was associated with an increased risk of cardiovascular death, but was just barely statistically significant. But supplements of more than 1,000 mg/day were associated with a highly significant increase in cardiovascular mortality:

(mg/day)  
None 1.00
< 400 .99 (.94-1.04)
400–1,000 1.09 (1.01-1.18)
> 1,000 1.20 (1.05-1.36)

When the numbers were stratified for smoking, there was a strong trend towards the risk being mainly in current smokers. The average user of supplements for men had a dietary calcium intake (not including supplements) of 815 mg. So once you figure in another 400 to 1,000+ mg of supplemental calcium, their intakes were anywhere from the DRI to about 50% higher than the DRI.

The second study was from Sweden, on older women (2). All-cause mortality for dietary calcium (not including supplements) was a U-shaped curve, with both low calcium and high calcium associated with an increase in mortality:

(mg/day)  
< 600 1.38 (1.27, 1.51)
600-999 1.00
1000-1399 1.00 (.96-1.04)
≥ 1,400 1.40 (1.17-1.67)

The findings were similar, but even stronger for cardiovascular disease, and were also very similar for dietary plus supplemental calcium.

One thing to consider for this Swedish study is that 1,400 mg of non-supplemental calcium would indicate a pretty high dairy intake. If you assume 300 mg per serving of dairy, that’s at least 3 servings of dairy per day (on top of the calcium they might be getting from other foods). The results did not adjust for dairy product intake so it’s possible that dairy of 3 servings (or more) per day could have caused the increase in cardiovascular deaths.

While it’s not yet clear what is going on here, my conclusion remains that vegans should aim for at least 700 to 1,000 mg/d (or 700 to 1,200 mg/d if over 50) from foods or supplements, but that you should not go much above that.

Support JackNorrisRd.com

I greatly appreciate direct donations – you can enter any amount:

If button doesn’t work, please click through to website. Thank you!

If you buy anything from Pangea through this link, you not only support me, but also the good people at Pangea who painstakingly research their products to minimize any impact on animals, the earth, and workers.

Amazon.com Gift Cards – E-mail Delivery

Vegan for Life: Everything You Need to Know to Be Healthy and Fit on a Plant-Based Diet from Amazon.com

References

1. Xiao Q, Murphy RA, Houston DK, Harris TB, Chow W, Park Y. Dietary and Supplemental Calcium Intake and Cardiovascular Disease Mortality: The National Institutes of Health–AARP Diet and Health Study. JAMA Intern Med. 2013;():1-8. | link

2. Michaëlsson K, Melhus H, Warensjö Lemming E, Wolk A, Byberg L. Long term
calcium intake and rates of all cause and cardiovascular mortality: community
based prospective longitudinal cohort study. BMJ. 2013 Feb 12;346:f228. | link

What B12 Supplement Should I Take?

Thursday, December 27th, 2012

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.

Sublingual B12 no better than just swallowing

Friday, April 6th, 2012

Question (edited for clarity):

It is always explicitly recommended that Vitamin B12 tablets should be dissolved under the tongue (aka “sublingual”). I wonder if that is also true for other minerals and vitamins of special concern to vegetarians, such as iron and vitamin D2? If not, why is this the case with vitamin B12?

Answer:

I have always told people who asked about sublingual B12 that there was no evidence, of which I was aware, that sublingual was any better than just chewing. Despite this, until today, I had been recommending sublingual in my Step 1 Recommendations, which are geared towards people who have not recently had a reliable source of B12. I have recommended sublingual as a precaution just in case it was more effective. In recent years, I have been more diligent about trying not to recommend anything just to be prudent unless specifically stating that is why I am recommending it. This suggestion for sublingual (versus just oral) was a remnant left over from previous times.

Still, I did not know whether sublingual was better than oral until I got this question and decided to check in on the research. As it turned out, there was a study as long ago as 2003. Yikes! I guess I hadn’t checked in quite a long time.

The 2003 study compared 500 µg per day via the sublingual and oral routes. The results were that sublingual was absolutely no better than oral B12 at raising vitamin B12 levels or improving B12 activity (as measured by homocysteine and methylmalonic acid levels). The report did not specifically state whether the tablets were chewed or not (I assume that they were swallowed whole). So now I’m not sure I should even suggest that the tablets be chewed, but because other studies have shown a benefit to chewing, I will leave that in my recommendations.

As for other vitamins and minerals, I have never checked into the research on taking them via the sublingual route, but my sense is that there would not be any benefit. It might even be dangerous to try this with iron given that it is a pro-oxidant and probably should not be held in constant contact with your tissues.

Reference

Sharabi A, Cohen E, Sulkes J, Garty M. Replacement therapy for vitamin B12 deficiency: comparison between the sublingual and oral route. Br J Clin Pharmacol. 2003 Dec;56(6):635-8. | link

Harvard: Multivitamin Still a Good Idea

Monday, December 19th, 2011

Harvard School of Public Health: Nutrition Insurance Policy: A Daily Multivitamin

From the article:

“Looking at all the evidence—from epidemiological studies on diet and health, to biochemical studies on the minute mechanisms of disease—the potential health benefits of taking a standard daily multivitamin appear to outweigh the potential risks for most people.”

They reference the Iowa Women’s Health Study which I blogged about on October 11.

(Note: I am not able to recommend or assess any particular brand of multivitamin.)

Supplement Safety

Tuesday, October 11th, 2011

A new report on the safety of supplement use in older women has been released from the Iowa Women’s Health Study (1).

The study tracked women 55 to 69 years old, almost entirely white, for an average of 19 years. After adjusting for age, education, place of residence, diabetes, high blood pressure, body mass index, waist to hip ratio, hormone replacement therapy, physical activity, smoking, energy, alcohol, saturated fatty acids, whole grain products, fruits, and vegetables, they found the following:

– Multivitamins were associated with a 6% increase in mortality (1.06, 1.02-1.10).

– Iron (1.10, 1.03-1.17) and copper (1.45, 1.20-1.75) were associated with an increased risk for mortality.

– Vitamin B6 (1.10, 1.01-1.21), folic acid (1.15, 1.00-1.32), magnesium (1.08 1.01-1.15), and zinc (1.08, 1.01-1.15), were all associated with a borderline statistically significant increased risk of mortality.

– Vitamin A, beta-carotene, vitamin B complex, vitamin C, vitamin D, vitamin E, and selenium supplements were not associated with an increase in mortality.

– Calcium supplements were associated with a decreased risk of mortality (0.91, 0.88-0.94).


This Post Sponsored By ‒

NutritionFacts.org: The latest in nutrition research with a new video uploaded daily!


There was not a lot of data on amounts, except for iron and calcium. The groups with an increased risk of mortality from iron were taking fairly hefty amounts of iron, with the biggest risks associated with 50 to > 400 mg/day! That is a lot of iron ‒ the RDA for women 51 to 70 years old is 8 mg.

The levels of calcium associated with the reduced risk of mortality were basically anything less than 1,300 mg per day.

The authors summed up their findings with, “In conclusion, in this large prospective cohort of older women, we found that most dietary supplements were unrelated to total mortality rate. However, several commonly used dietary vitamin and mineral supplements were associated with increased total mortality rate, most strongly supplemental iron; calcium showed some evidence of lower risk.”

This study is just one piece to a very large puzzle, and I would not take it to mean anything conclusive. If you look at the entire body of research, results regarding supplements have been quite mixed and this tends to make me think they do not have a strong effect on mortality one way or the other, although there is still more to be learned.

One thing I would take away from this study is that it is further evidence that people should not take iron supplements, especially more than the RDA, unless under the guidance of a physician.

As for vegans, studying supplements in terms of their ability to decrease or increase mortality in a population that does not have acute deficiencies is not the same as for people whose diets are significantly lower than the DRIs for particular nutrients. This study would not give me any reason to change my recommendations.

Reference

1. Mursu J, Robien K, Harnack LJ, Park K, Jacobs DR. Dietary Supplements and Mortality Rate in Older Women: The Iowa Women’s Health Study. Arch Intern Med. 2011;171(18):1625-1633.   |   Link

Ginny Messina: Monitoring vs. Supplementing

Monday, September 19th, 2011

Ginny has once again set the record straight with her article, Vitamins B12 and D: Monitoring versus Supplementing.

I would merely add that if you are going to the doctor to get tests done anyway, it wouldn’t hurt to add vitamin D to the panel just to know where it is.

Bill Clinton, are you listening?!

Taurine and Vitamin D

Monday, January 3rd, 2011

Happy New Year!

I have a couple of quick things which might be of interest:

1. After reading that QuasiVegan was taking taurine and feeling great, I decided to do some experimenting on myself. I have been taking 1,000 mg of taurine per day for a week. I don’t feel any different – not that I was feeling bad to begin with, but you never know.

A few years ago I tried a similar experiment with carnitine and I noticed myself feeling slightly worse. Also a few years ago, I tried taking methylcobalamin (a form of vitamin B12) rather than cyanocobalamin and felt nothing after going through an entire bottle over the course of a few weeks.

2. Over the holidays I talked to another vegan who was feeling very fatigued, got her D levels tested and they were low, started taking vitamin D, and now feels much better.

I’m not suggesting that how one feels is the best way to determine if taking a supplement is healthy or not, but it might be able to indicate if you had a severe deficiency.

DHA Supplements: A Good Idea, Especially for Older Vegan Men

Monday, November 8th, 2010

My October 22 post about Doug Graham’s B12 claims garnered a lot of comments. Among them was one suggesting that I am alarmist at times. So, it is with hesitation that I report the following.

Background: If you are not familiar with omega-3 fatty acids, some of the conversation below might not make much sense. See Omega-3 Fatty Acid Recommendations for Vegetarians for background.

DHA in Elderly Vegan Men

I have been in dialogue with Dr. William Harris about DHA. Dr. Harris has been vegan for many decades and will be 80 years old this December. He has been concerned about making sure he has enough DHA, but in the past when he took DHA, he started bruising very easily. A more recent report from him is that he has been trying DHA again and the bruising has not reappeared.

Dr. Harris cc’d me on a discussion he was having with Dr. Joel Fuhrman and this led me to find out from Dr. Fuhrman that he has been seeing numerous elderly vegans with severe DHA deficiency, and he believes it may have exacerbated Parkinson’s disease and tremors in some of his patients. Upon more questioning, Dr. Furhman had the following to say:

“I have seen thousands of vegan patients, raw foodists, natural hygienists, McDougall and Ornish participants, as well as my own ‘nutritarian clients’ over the last 20 years. I test B12 on everyone, of course we are not talking about B12 [deficiency in regards to the patients with Parkinson's and tremors], these individuals were well-educated about B12. I have seen some paralysis and other major B12 problems in hygienists and vegan raw foodists. Some that even died from hyperhomocysteine resulting from severe B12 deficiency. I have also seen vegans with balance and ambulation issues with B12 deficiency, unable to walk. One raw foodist who came to see me with this problem, who could not walk, made almost a complete recovery after B12 supplements and then he announced on his radio show that he recovered from M.S. with a raw food diet. ”

“Many of the visits were initiated by complaints. Many people who started or adopted vegan diets went back to eating meat after suffering from fatty acid deficiency symptoms from not eating sufficient seeds and nuts. I have performed fatty acid tests, B12, MMA, amino acid profiles and others on many people. I have seen significant DHA and EPA deficiencies even in middle aged women, but the most predictable pattern is the dramatically low levels in elderly vegan men. I do feel to err on the side of caution, either a blood test to confirm adequacy or a low dose of DHA is indicated, and, as was discussed, you do not need very much [200 – 300 mg DHA per day for one month] to fix the blood test findings.”

Because of the above conversation, I have tweaked my DHA recommendations for vegans, emphasizing that elderly vegans need to take more:

    Under 60 years old: 200 – 300 mg every 2-3 days
    60+ years old, pregnancy, or breastfeeding: 200 – 300 mg per day

This amount may be somewhat more than necessary, but until we know what level can sustain DHA levels long term, it seems like the most prudent amount. This is based both on what Dr. Fuhrman says above, as well as a 2003 study that showed blood levels of DHA to increase 48% in vegans taking 200 mg per day for 3 months (1).

Vegans Convert DHA Better than Fish Eaters

In other DHA news, a study from EPIC-Norfolk recently came out showing that while vegans have lower levels of DHA in their blood, they are more efficient at converting ALA to DHA than people who eat fish (2). This is not surprising, as an abstract by the same lead author was published in 2008 finding the same thing. You can see the EPA and DHA levels in Table 4 of Omega-3 Fatty Acid Recommendations for Vegetarians.

There were only 5 vegan men and 5 vegan women in this study. Despite the higher conversion rate, the vegan men still had significantly lower DHA levels than the fish-eaters. However, the vegan women actually had the highest DHA levels of any diet group (although the standard deviations was quite large indicating that some of the women had very high levels and some had very low). The authors did not address this unusual finding.

Omega-3 Lab Tests

If you are interested in getting your DHA levels tested, Dr. Harris has compiled a list of three labs he was able to find that test them. Dr. Harris was only completely confident in the results from Mayo Clinic.

1. Mayo Labs – $394.60 for 29 different fatty acids including LA, AA, ALA, EPA, and DHA

2. MetaMetrix – $206 for 7 fatty acids

3. Genova – $188.65 for 4 Omega-3 and 6 Omega-6 fatty acids

I am not suggesting that all vegans need to get their DHA levels tested and I do not know anything further about these tests. I am just providing them for people who might be interested.

References

1. Lloyd-Wright Z, Preston R, Gray R, Key TJA, Sanders TAB. Randomized placebo controlled trial of a daily intake of 200 mg docosahexaenoic acid in vegans. Abstracts of Original Communications. Proceedings of the Nutrition Society 2003:42a. (No link available.)

2. Welch AA, Shakya-Shrestha S, Lentjes MA, Wareham NJ, Khaw KT. Dietary intake and status of n-3 polyunsaturated fatty acids in a population of fish-eating and non-fish-eating meat-eaters, vegetarians, and vegans and the precursor-product ratio of alpha-linolenic acid to long-chain n-3 polyunsaturated fatty acids: results from the EPIC-Norfolk cohort. Am J Clin Nutr. 2010 Nov;92(5):1040-51. Link

Can My Recommendations Prevent Failure to Thrive?

Wednesday, June 9th, 2010

A couple weeks ago, I was made aware of the website and blog, Let Them Eat Meat, written by Rhys Southan. He had mentioned me in a post and someone forwarded it to me. I spent a few minutes looking around the site and found it very interesting. Rhys is an ex-vegan and the site is basically a criticism of many aspects of the vegan movement, some of which I can’t say I disagree with. He was vegan for many years, didn’t feel healthy, mentally or physically, and went back to eating meat and felt a lot better.

In a post of June 7, Rhys says that some vegans are claiming that if you follow my nutrition recommendations, you will not fail as a vegan. He goes on to say:

There was a point when I was lazy about B12 pills and relied on supplemented nutritional yeast and soy milk (the vegan health argument at that time downplayed the need for B12, which convinced me this was adequate), but I got into taking B12 more regularly after enduring Restless Legs Syndrome for a few months.

Still, I didn’t follow Norris’ exact recommendations. For one thing, I didn’t know who the hell he was. And even if I had, Norris is constantly revising his recommendations in response to new research, and the B12 dosage Norris now stands behind was posted in March of this year, so that wouldn’t have helped anyway.

I would like to clarify some of this:

1. Though my recommendations have helped many people (who were not coming even close to following them), I do not think that following them insures that someone will have no trouble being vegan.

2. My recommendations do not need to be followed exactly to get most of the benefit. If you followed my pre-March vitamin B12 recommendations, you should not feel any different in the short term than following the new recommendations. Tweaking my B12 recommendations is for preventing long-term, chronic disease, not for daily feelings of well-being.

3. For the main nutrients I focus on (B12, omega-3s, vitamin D, calcium, iodine, vitamin A), I probably change my recommendations for any given nutrient no more than once every 5 years, and I rarely change them by much. My vitamin B12 recommendations change in March was the first I’ve made since about 2003.

4. If new evidence shows me that my recommendations need to be changed, I change them.

5. Restless leg syndrome could very well be from a vitamin B12 deficiency and my recommendations now or at the time might have helped this aspect of Rhys’ health; and it’s possible they could have even improved his mental issues as well. But, that said, see #1 above.

I am interested in reading more of Rhys’ site and possibly responding to things I find of interest, such as the below. Perhaps this is a good place for me to state for any new readers that I am a vegan to prevent animal suffering. There are some worthwhile health benefits, but those are side-benefits for me.

Rhys states in his post linked above:

In my case, when I grocery shop, I buy mostly organ meats. And when I go to a restaurant, I look for the organ option the way a vegan looks for the vegan option. I do this because I think fewer animals will need to be raised and killed if more of the animal parts are used. In that sense, I am accomplishing exactly what vegans are — fewer animals are being born. (But I recognize that my consumer choices are almost totally insignificant in this regard; like veganism, this is a symbolic gesture).

That’s probably true – just like in voting, your vote is unlikely to make a difference. But if enough vegans create a critical mass such that less animals are raised, it is probably in proportion to how many vegans there are and, at that point, one vegan could make a real difference to some animals.

 
Please note that I don’t allow comments through that are impolite or disrespectful.