Author Archive

B12 & Iron Deficiency in an Italian Vegan Infant

Tuesday, June 26th, 2012

Sadly, a report was published today of a vegan mother in Italy whose infant developed B12 deficiency and the typical neurological issues that go along with it.

The mother had taken a multivitamin with 2.5 µg of B12 during her 2nd and 3rd trimester. The baby had been born small (3rd percentile for weight). He was then exclusively breast fed and the mother ceased the multivitamin.

The infant developed both B12 and iron deficiency by five months. Seven months of treatment with B12 and iron resulted in drastic improvement in neurological symptoms, but not a full recovery at that time.

The case underscores the need for exclusively nursing mothers to ensure they have a reliable source of vitamin B12 so that their breast milk has adequate amounts. A baby should be born with iron stores to last 6 months, but this boy was not. Not much information was given about any attempts to monitor the mother’s iron levels during pregnancy or the baby’s after birth ― apparently not much was done.

I’m hoping for some better vegan health news as the week progresses…

Reference

Guez S, Chiarelli G, Menni F, Salera S, Principi N, Esposito S. Severe vitamin B12 deficiency in an exclusively breastfed 5-month-old Italian infant born to a mother receiving multivitamin supplementation during pregnancy. BMC Pediatr. 201 Jun 24;12(1):85. | link

German Vegetarians and Mental Disorders

Monday, June 25th, 2012

In June 2010 I blogged about a study showing that Seventh-day Adventist (SDA) vegetarians had “less negative emotions” than SDA non-vegetarians (link).

Earlier this month, a cross-sectional study from Germany was released showing that vegetarians were more likely to have had mild mental disorders. The purpose of the study had been to see if vegetarians who eat less fish (for DHA) and get less vitamin B12 were more likely than non-vegetarians to develop mental disorders. It turned out that while the vegetarians did have higher rates of mental disorders, they had, on average, developed them before becoming vegetarian.

Many of the vegetarians did eat fish, but excluding them did not change the results. It is not clear how many, if any, of the vegetarians were vegan, but definitely not more than half (the percentage who never ate fish).

The data was taken from the German National Health Interview and Examination Survey (GHS) conducted in 1998/1999, making me feel less bad that it took me two weeks to get around to writing a post about it.

They did find that the vegetarians were more likely to develop an eating disorder after they became vegetarian, whereas the rest of the disorders (depression, anxiety, somatoform (hypochondria and pain)) tended to occur before becoming vegetarian.

I originally read this study for the B12 and DHA angle. As I read it and found out that more than half of the “vegetarians” were actually semi-vegetarians, I became less enthused about reporting on it, but in the end decided I should in case it was mentioned elsewhere on the Internet.

Hopefully, things have improved for German vegetarians in the last 10 years.

Reference

Michalak J, Zhang XC, Jacobi F. Vegetarian diet and mental disorders: results from a representative community survey. Int J Behav Nutr Phys Act. 2012 Jun 7;9(1):67. (link)

Hypospadias and Vegetarian Diets

Thursday, June 21st, 2012

A report from the National Birth Defects Prevention Study (1) was recently released. Counter to two previous studies, it found no association between vegetarian diets in pregnant women and having a boy with hypospadias. This makes six studies examining the association to date with four finding no association.

This is great news, but we are not completely out of the woods yet. There is still reason to make sure that pregnant vegans cover all of their bases.

I have revamped the article Hypospadias and Vegetarian Diets on VeganHealth.org where you can read the fine print.

Reference

1. Carmichael SL, Ma C, Feldkamp ML, Munger RG, Olney RS, Botto LD, Shaw GM, Correa A. Nutritional factors and hypospadias risks. Paediatr Perinat Epidemiol. 2012 Jul;26(4):353-60. (link)

Reed Mangels on Folic Acid vs. Food Folate in Pregnancy

Wednesday, June 20th, 2012

Folic Acid in Pregnancy

Excerpt:

“Bottom line (my opinion): We don’t have enough information to recommend food folate in place of folic acid to reduce risk of neural tube defects. Based on what we know now, the benefits of folic acid supplements prior to conception and during pregnancy outweigh the risks.”

More B12 Claims

Saturday, June 16th, 2012

An activist brought to my attention the article B12 Deficiencies in Vegans? Not True! at Flaming Vegan. I was surprised to read the article and the comments, and so I posted some comments of my own below it.

Another reader brought my attention to a page claiming that miso is a source of vitamin B12 and that chlorella is the “best source” of vitamin B12.

As for miso, the two published studies that have measured vitamin B12 in miso have found none. As for chlorella, two studies have found vitamin B12 in batches of chlorella while one study found practically none. Chlorella might be a source of vitamin B12, but there has yet to be any studies in the scientific literature to determine if chlorella can improve vitamin B12 status (see B12 in Tempeh, Seaweeds, Organic Produce, and Other Plant Foods for citations).

It is not clear why chlorella would have vitamin B12 – whether through contamination or because it actually produces it, and because of this, multiple batches from different locations should be tested before there is any certainty that it is a reliable source.

It should also be noted that the second link above lists romaine and arugula as sources of calcium. According to the USDA, one cup of shredded romaine has only 15 mg of calcium and one cup of arugula has 32 mg of calcium. So if you are going to rely on either for calcium, you will need to eat many servings.

2012 meta-analysis on veg mortality and cancer incidence

Tuesday, June 12th, 2012

A new meta-analysis on vegetarian mortality and cancer has been released (1). It found a statistically reduced rate for vegetarians in terms of ischemic heart disease mortality and cancer incidence. It did not find a difference for all cause mortality or stroke.

Comments I have added to Disease Rates of Vegetarians and Vegans on VeganHealth.org:

“Although the 2012 meta-analysis by Huang et al. (1) is more recent, it may not be as reliable as the 1999 meta-analysis [by Key et al.] because it includes a 1984 study on Zen priests (2) who were mostly semi-vegetarian and which used a standardized mortality ratio (comparing all the Zen priests to the greater population rather than comparing the “vegetarians” to non-vegetarians within the same group). The Heidelberg Study results were also included and its control group was semi-vegetarians, which means there were semi-vegetarians in both the “vegetarian” and “non-vegetarian” group in the 2012 meta-analysis; while this is not ideal, it should have biased the results against finding a beneficial effect of a vegetarian diet. In its favor, the 2012 meta-analysis includes data from EPIC-Oxford that was not available for the 1999 meta-analysis.”

There is a table with the confidence intervals at the link above.

Reference

1. Huang T, Yang B, Zheng J, Li G, Wahlqvist ML, Li D. Cardiovascular Disease Mortality and Cancer Incidence in Vegetarians: A Meta-Analysis and Systematic Review. Ann Nutr Metab. 2012 Jun 1;60(4):233-240. (Link)

2. Ogata M, Ikeda M, Kuratsune M. Mortality among Japanese Zen priests. J Epidemiol Community Health. 1984 Jun;38(2):161-6. (Link)

Omega-3s in Vegetarian Diets

Thursday, June 7th, 2012

The article I wrote, Omega-3’s: Are You Getting Enough?, for the Made Just Right blog had to be removed due to legal concerns regarding giving health advice, so I am reprinting it here. And I added a short section on children towards the end.

Summary

There is strong evidence that omega-3 fatty acids are useful in the prevention and treatment of heart disease. There is also some evidence that they might be important for cognitive function or useful as a treatment for depression. While short-chain fatty acids are found in a variety of plant and animal foods, fish provide the main source of the long-chain omega-3s. There are also long-chain omega-3 vegan supplements made from seaweed. Especially in the case of older vegetarians, there is a concern that an omega-3 deficiency could cause cognitive problems and omega-3 supplementation is recommended.

Background on Omega-3s

There are three important omega-3 fatty acids:

1. α-linolenic acid (ALA) is a short chain fatty acid. It is found in small amounts in animal flesh, in very small amounts in a variety of plant products, and in relatively large amounts in soy, walnuts, canola oil, camelina oil, and in flax, hemp, and chia seeds and their oils. The human body cannot make its own ALA, it is an essential fatty acid that must be obtained through the diet.

2. Eicosapentaenoic acid (EPA) is a long chain fatty acid. It is found in large amounts in fatty fish, in small amounts in eggs, and in very small amounts in seaweed. Some EPA is converted into other molecules that can reduce blood clotting, inflammation, blood pressure, and cholesterol.

3. Docosahexaenoic acid (DHA) is a long chain fatty acid. Like EPA, it is found in large amounts in fatty fish, in small amounts in eggs, and in very small amounts in seaweed. It is a major component of the gray matter of the brain, and also found in the retina, testis, sperm, and cell membranes.

All three of these omega-3 fatty acids may prevent heart arrhythmias, though ALA has been studied the least in clinical trials.

The body can convert ALA into EPA, and EPA into DHA. ALA is efficiently converted to EPA, but it may require large amounts of ALA to produce optimal amounts of DHA.

Health Benefits

The American Heart Association (AHA) recommends that adults eat at least two servings of fatty fish a week. The AHA says that people with coronary artery disease may want to talk to their doctor about fish oil supplements, and, especially for people with high triglycerides, large doses of fish oil could help.

An ALA intake of about 2 g/day has been consistently associated with a modest lowering of heart disease risk.

There is evidence that EPA and/or DHA supplementation may improve depression and cognition, particularly in infants, children and older adults, although the results of clinical trials have been mixed.

Vegetarians and Omega-3 Status

Vegetarians, including vegans, have been shown in many studies to have lower levels of EPA and DHA than meat eaters. We do not know if lower blood DHA levels reflect lower levels in other tissues in vegetarians, though it is a reasonable assumption.

Because EPA reduces blood clotting, one way to figure out if vegetarians are getting enough EPA is to compare the blood clotting parameters of vegetarians to omnivores. Two studies have done this and found the differences to be minimal.

Vegetarians already have about a 24% lower risk of heart disease than regular meat-eaters and on average have lower triglyceride levels, and it is not clear that EPA or DHA supplementation will further reduce their risk.

In terms of depression and cognition, there has been no research on omega-3s and vegetarians, but Joel Fuhrman, MD, has a private practice seeing many long-term vegans and has observed some older vegan men with very low DHA levels and cognitive problems, so there is reason to be prudent regarding DHA in older vegans, especially men.

Improving Omega-3 Status in Vegetarians

The traditional way that vegetarians were encouraged to raise EPA and DHA levels was by increasing ALA and decreasing linoleic acid (LA), a short chain omega-6 fatty acid. Although the body can convert ALA into EPA, the enzymes that do this also convert LA into longer chain omega-6s. If there is too much LA in the diet, the enzymes can be saturated with LA and unable to convert omega-3s. An ideal ratio of omega-6 to omega-3 in the diet is thought be about 3 or 4. Vegans tend to have a ratio of 10 to 15 compared to a ratio of 6 to 10 for omnivores.

To deal with this problem, in the late 90s and 00s, vegetarian health professionals recommended increasing ALA intake and decreasing LA intake. Unfortunately, there are no long-term studies looking at the EPA and DHA levels in vegetarians who follow these recommendations. Research shows that 3 – 4 g of ALA per day per day can increase DHA levels; assuming intake of omega-6 is low.

Increasing ALA to 3 – 4 g/day has some concerns. Three studies looking at age-related eye damage and fatty acids, all coming from the Nurse’s Health Study, have associated modest ALA intakes with age-related eye problems. The ALA in these studies came mostly from animal products that were likely cooked (omega-3s are easily oxidized by heating). It is not clear that the association is causal or if the causation would apply to uncooked ALA (i.e., from plants).

Although ALA has been associated with prostate cancer risk in some studies, the association has been shown with a fair degree of certainty not to be causal.

If it weren’t for the (small chance) for potential eye problems, my recommendations would be either to add 3 g of ALA per day or to take a DHA supplement. Because of the chance for eye damage, that much ALA is not worth the risk when DHA supplements are available and more effective. Vegetarians should still add .5 g of ALA per day for its benefits on heart disease and to help increase EPA levels. Such small amounts of uncooked ALA should pose no risk to the eyes.

Recommendations

Following all three of these recommendations should keep vegans on par with fish eaters:

1. Take a DHA Supplement

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

2. Do not prepare food with oils high in omega-6 such as corn, soy, safflower, sunflower, most vegetable oil blends (typically labeled “vegetable oil”) and sesame oil. Instead, use low omega-6 oils like olive, avocado, peanut, or canola.

3. On average, vegetarians meet about 50 to 60% of the daily ALA recommendations without special diet planning and should add 0.5 g of uncooked ALA daily. This would be the equivalent of:

1/5 oz *English walnuts (3 halves)
1/4 tsp of flaxseed oil
1 tsp of canola oil
1 tsp ground flaxseeds

*English walnuts are the typical walnuts for sale in grocery stores. They are distinct from black walnuts.

Too much omega-3 can result in bleeding and bruising. If you have reason to believe you have problems with easy bleeding or bruising consult a health professional before increasing your omega-3 intake.

Vegan DHA & EPA Supplements

There are now many companies offering vegan DHA supplements made from seaweed. Some of them include EPA. Some DHA can be converted into EPA and if you are supplementing your diet with .5 g of ALA, you probably do not need a DHA supplement that also contains EPA, but there’s no harm from doing so.

Vegetarian Children and DHA

There is a concern that dietary DHA may be important to developing fetuses and infants. Anthropologist John H. Langdon argues that DHA is not an essential nutrient for the brain development of infants. Pregnant women efficiently convert ALA to DHA and fetuses and infants are able to receive DHA that is released from the mother’s fat tissues and provided through the umbilical cord or breast milk. Langdon argues that in cases of very low maternal levels of DHA, infants can utilize other fatty acids for brain tissue that can later be replaced by DHA.

In a study comparing breast milk, cow’s milk formula with DHA, soy formula with DHA, and soy formula without DHA, infants who ate soy formula without DHA had indications of slower parasympathetic development, though still within the normal range.

A 1994 study measured the DHA levels in the umbilical cords of 32 infants born to vegetarian mothers compared to omnivores, and revealed no relationship between DHA and the birth weight or head circumference of the infants.

Many children have been raised vegan without supplementing with DHA, or even extra ALA, and appear to develop well. Despite this, parents of vegetarian children are encouraged to supplement their diets with DHA at 200 mg every two or three days until more is known about DHA in vegan infants.

Flax & Chia Facts

Flax

• Flaxseeds are the most concentrated source of alpha-linolenic acid (ALA), with an omega-6 to omega-3 ratio of 1:4.

• One teaspoon of flaxseed oil contains 2.5 g of ALA.

• One tablespoon of ground flaxseeds contains 1.6 g of ALA.

• If flaxseeds are not ground, they will not be digested. They can be ground in a blender or coffee grinder, and then stored in the freezer. Ground flaxseeds can be sprinkled on cereal or used in baked goods.

• Cooking flaxseed oil damages the ALA, but it can be put on warm food such as toast. Flaxseed oil should be kept in the refrigerator.

• A straight teaspoon of flaxseed oil does not taste so great. Some people use cinnamon-flavored oil, tablets, or put it on toast or salad to make it taste better.

Chia

• Chia (Salvia hispanica; also known as Salba) seed oil is a good source of ALA.

• Dried chia seeds have 5 g of ALA per ounce, with an omega-6 to omega-3 ratio of 1:3.

More Information

This article is an abridged version of Omega-3 Fatty Acid Recommendations for Vegetarians which is fully annotated.

In addition to a short article I’ve written, Fish and Cardiovascular Disease, The Linus Pauling Institute at Oregon State University provides an in-depth review of omega-3s and heart disease in Essential Fatty Acids.

Fish and Cardiovascular Disease

Wednesday, June 6th, 2012

Epidemiologists have observed a low risk of coronary heart disease mortality among native Alaskan and Greenland Eskimos and Japanese who consumed a large amount of fish (3). This led researchers to take an interest in fish and fish oil supplementation in the prevention and treatment of heart disease. At the same time, Eskimos have been found to have a high rate of hemorrhage (4), a risk factor for hemorrhagic stroke, which is also likely due to eating large amounts of fish.

In April, PCRM sent out a news release, Fish Oil Does Not Prevent Heart Disease, reporting on a meta-analysis of fish oil supplement trials. I decided to look into it more, and here is what I found.

Secondary Prevention

In April 2012, a meta-analysis of clinical trails using fish oil supplements to treat heart disease was reported in the Archives of Internal Medicine (conducted by the Korean Meta-analysis Study Group (1)). It combined data from 14 randomized, double-blinded, placebo-controlled trials and found that supplementing with fish oil did not reduce the risk of overall cardiovascular events, all-cause mortality, sudden cardiac death, myocardial infarction, congestive heart failure, transient ischemic stroke, or overall stroke in people with a history of cardiovascular disease.

The results of this study contradicted two large clinical trials with fish oil supplements, the Gruppo Italiano per lo Studio della Sopravvivenza nell’Infarto Miocardico (GISSI) and the Japan EPA Lipid Intervention Study. Both of these studies found a protective effect of fish oil supplementation, but they were not included in the meta-analysis because they did not contain a placebo group. In an accompanying editorial (2), Drs. Frank Hu and JoAnn Manson of the Harvard School of Public Health argued that due to the studies in the meta-analysis having relatively small numbers of people, the evidence from these two larger clinical trials should not have been completely ignored. But, Drs. Hu and Manson also conclude that “To date, there is no conclusive evidence to recommend fish oil supplementation for primary or secondary prevention of [cardiovascular disease].”

Primary Prevention

The above discussion is about secondary prevention, or preventing cardiovascular events in people who have already been diagnosed with cardiovascular disease. According to the Korean Meta-analysis Study Group, there have not been any primary prevention studies of fish oil supplementation in a population free of cardiovascular disease at baseline.

As distinct from fish oil supplementation, there have been two meta-analyses on fish consumption and primary prevention of heart disease (3) and stroke (4). Both were conducted by the Northwestern University Feinberg School of Medicine.

The meta-analysis on fish intake and heart disease combined data from 13 cohort groups and found that eating fish once per week could significantly reduce death from coronary heart disease by 15% in comparison to eating fish less than once per month. The trend for non-fatal heart attacks was not strong nor statistically significant.

The meta-analysis on fish and stroke combined data from nine cohort groups and found that eating fish one to three times per month was protective against ischemic stroke (in which a blood clot prevents the brain from receiving blood), which makes up 87% of strokes. Fish intake was not protective against hemorrhagic stroke (in which bleeding in the brain causes pressure on the brain tissue). See the American Stroke Association’s website for some interesting illustrations of the different types of stroke.

Conclusion

Based on the available evidence, moderate amounts of fish appear to be protective against heart disease and ischemic stroke, but fish oil supplementation probably does not prevent heart disease events or death in people already diagnosed with heart disease.

I am not suggesting people eat fish and it’s worth noting that a vegetarian diet has been associated with a 24% lower risk of heart disease mortality (link). I recommend that most vegans take a DHA supplement to make sure they are on par with fish eaters (link).

References

1. Kwak SM, Myung SK, Lee YJ, Seo HG; for the Korean Meta-analysis Study Group. Efficacy of Omega-3 Fatty Acid Supplements (Eicosapentaenoic Acid and Docosahexaenoic Acid) in the Secondary Prevention of Cardiovascular Disease: A Meta-analysis of Randomized, Double-blind, Placebo-Controlled Trials. Arch Intern Med. 2012 Apr 9. [Epub ahead of print] | link

2. Hu FB, Manson JE. Omega-3 Fatty Acids and Secondary Prevention of Cardiovascular Disease–Is It Just a Fish Tale?: Comment on “Efficacy of Omega-3 Fatty Acid Supplements (Eicosapentaenoic Acid and Docosahexaenoic Acid) in the Secondary Prevention of Cardiovascular Disease”. Arch Intern Med. 2012 Apr 9.
[Epub ahead of print] | link

3. He K, Song Y, Daviglus ML, Liu K, Van Horn L, Dyer AR, Greenland P. Accumulated evidence on fish consumption and coronary heart disease mortality: a meta-analysis of cohort studies. Circulation. 2004 Jun 8;109(22):2705-11. | link

4. He K, Song Y, Daviglus ML, Liu K, Van Horn L, Dyer AR, Goldbourt U, Greenland P. Fish consumption and incidence of stroke: a meta-analysis of cohort studies. Stroke. 2004 Jul;35(7):1538-42. Epub 2004 May 20. | link

Vegetarian Diet associated with Younger Age of Menopause

Wednesday, May 30th, 2012

A cross-sectional study from the United Kingdom (the Breakthrough Generations Study) found that self-described vegetarians were more likely to have an earlier age of natural menopause. In turn, a lower age of menopause has been associated with lower rates of breast cancer.

The authors wrote:

“Vegetarians reached menopause at a mean age of 50.1 years, which was significantly earlier than non-vegetarians (mean menopausal age = 50.7 years, HR = 1.12; P < 0.001). The effect was present regardless of whether the woman became vegetarian before 20 years of age or between the ages of 20 and 40 years (data not shown)." This confirms previous reports that vegetarians have a lower age of menopause. Reference

Morris DH, Jones ME, Schoemaker MJ, McFadden E, Ashworth A, Swerdlow AJ. Body mass index, exercise, and other lifestyle factors in relation to age at natural menopause: analyses from the breakthrough generations study. Am J Epidemiol. 2012 May 15;175(10):998-1005. | link

Study on Omega-3s Looking for Older Vegans

Tuesday, May 29th, 2012

Research study: Age and Gender Differences in Essential Fatty Acids in Long-term Vegans

Do you follow a vegan diet? Are you interested in participating in a research study that will reveal your level of healthy omega-3 fatty acids?

Omega-3 fatty acids (EPA and DHA) are important nutrients that protect against risk for heart disease, depression, and dementia. The purpose of this study is to determine whether there are age and gender differences in blood levels of the essential fatty acids, EPA and DHA, in long-term vegans.

If you have been a vegan for at least 3 years, are a man 70 or older or a woman 80 or older (we have already filled the quota for the younger age groups) and you are not using essential fatty acid supplements, you may be eligible to participate in this study. The study involves providing information about your actual dietary intake on three separate days and a one-time finger stick blood sample you will send to a lab using a pre-paid envelope. It should take about 3 hours of your time to be in this study.

You will receive a $20.00 Target gift card and a report of your blood levels of essential fatty acids.

Please note, we are only enrolling men 70 and older and women 80 and older at this time. If you are interested, please visit Enroll in DHA Study for further information.

This study has been approved by the University of San Diego Institutional Review Board. The Principal Investigators are Barbara Sarter, PhD, APRN, FNP-C, Hahn School of Nursing and Health Sciences, University of San Diego and Joel Fuhrman, M.D., Research Director of the Nutritional Research Project.

This project is supported by the Nutritional Research Project.