I just updated VeganHealth.org’s articles on bones and homocysteine with the following:

Vitamin B12 and Bone Mineral Density

Taking vitamin B12 might also be important for bone mineral density.

A 2009 cross-sectional study of lacto-ovo vegetarian women in Slovakia found that their higher homocysteine (16.5 vs. 12.5 µmol/l; 78% vs. 45% were elevated) and lower vitamin B12 levels (246 vs. 302 pmol/l; 47% vs. 28% were deficient) were associated with significantly lower bone mineral density in the femur (1). Participants were not allowed to have been taking vitamin or mineral supplements. The researchers did not measure calcium intake or vitamin D status.

You can read more about vitamin B12 and homocysteine here.

1. Krivosikova Z, Krajcovicova-Kudlackova M, Spustova V, Stefikova K, Valachovicova M, Blazicek P, Nemcova T. The association between high plasma
homocysteine levels and lower bone mineral density in Slovak women: the impact of vegetarian diet. Eur J Nutr. 2009 Oct 7.

I just updated Another Internet Soy Article with the following:

A 2009 report from the Shanghai Breast Cancer Survival Study showed that women with a prior diagnosis of breast cancer (including estrogen-positive), who ate more soy, had lower rates of death and cancer recurrence (12). The study followed women for an average of 3.9 years after a diagnosis of breast cancer. The researchers measured a beneficial effect of up to 11 grams of soy protein per day. Table 3 shows the results.

12. Shu XO, Zheng Y, Cai H, Gu K, Chen Z, Zheng W, Lu W. Soy food intake and breast cancer survival. JAMA. 2009 Dec 9;302(22):2437-43.

After the posts I made regarding the article, A Whole Diet Approach to Building Better Bones, in the Vegetarian Voice, two people contacted me to say that the World Health Organization recommends more than the 400 to 500 mg of calcium per day as stated in the article. According to Table 4.2 on p. 71 in their document, Vitamin and Mineral Requirements in Human Nutrition, Second Edition (2004), the WHO recommends:

1,300 mg for ages 10 to 18
1,000 mg for women 19 to menopause
1,300 mg for women past menopause
1,000 mg for men 19 to 65
1,300 mg for men ages 65+

And if you missed them, there have been many comments in response to these two posts (link, link).

Because the comments section to my post, Comments on Bone Health Article in the Vegetarian Voice, has gotten so long, I decided to create a new post that includes Dr. Amy Joy Lanou’s response and my follow-up.

From Dr. Lanou:

“I appreciate that you have taken the time to read our article and critique it. I fear, though, that you may have missed the main point. Our overall point is that the literature is pointing to the benefits to bone of a dietary pattern that high in fruits, vegetables and other plant-matter and low protein from animal sources along with adequate weight bearing physical activity to stimulate new bone cell formation. In our book (Building Bone Vitality) we highlight the importance of consuming the at least 17 other nutrients that are important to bone (including adequate, but not excessive protein and vitamin D among 15 others) as part of a healthy dietary pattern based on whole foods from plant sources.

“The single nutrient, calcium, or single food (cow’s milk) approach to osteoporosis prevention that we have grown up with and are still being sold is not working and may even be counterproductive. Vegan nutritionists arguing over whether the actual amount of recommended calcium should be 400 to 500 mg/day as the World Health Organization recommends for avoiding osteoporosis, >525mg a day as the Appleby and Key study would suggest, or the 700 or 800 mg/day that Jack Norris, RD recommends is part of the problem….not part of the solution. We are still focusing on that same single nutrient.

“I agree that the literature is not clear on what the exact optimum amount of calcium that an individual vegan may need is…in fact, the “right amount” quite likely has to do with the persons overall dietary pattern, activity level and other individual characteristics. It is, however, quite clear to me from a broad review of the literature that vegans, vegetarians, and omnivores alike are not getting a measurable benefit to hip fracture from pushing calcium intakes via dairy products and calcium supplements from 1000 to 1200 to 1500 to 2000 mg a day as some professionals recommend. I purposefully chose not to make a personal (albeit expert) recommendation for the level of calcium for vegans to consume but instead chose to go with the recommendation of an authoritative source (the WHO) as a useful starting point. I have no argument against a person targeting a calcium intake of 800 milligrams in a whole foods vegan diet (though I would be surprised if it did help prevent fractures more than targeting 500 mg/day calcium intake.) I would suggest, however, that people taking 1000 mg of supplemental or dairy calcium a day (or more) to prevent osteoporosis stop doing so and look instead at putting their efforts instead into moving to a dietary and lifestyle pattern that supports bone health.

“Please keep in mind that Building Bone Vitality and the article in question were both written to help vegetarians and omnivores alike to understand that milk drinking is not necessary for healthy bones and to urge people to move to a diet built from health-giving and bone-supporting foods the fruits, vegetables and other plant foods and away from a diet that is built from highly processed foods, meat and cheeses. I understand that our message may not be detailed or specific enough for some clinicians and long time vegans. (I appreciate that clinicians are working to make sense out of the research and make more specific recommendations than we have.) I hope your readers will forgive us for this lack of specificity if we manage to do some good with the message (for human health, for the animals, and for the environment) along the way.

“A couple other points of clarification:

“We do address the Appleby study in the book, but not in the article. Dr. McDougall has written about the Appleby study as well and he notes that none of the fractures experienced by the vegans in this study were fractures of the hip compared to 30 in the meat eaters, 9 in the fish eaters, and 14 in the vegetarians (dairy). Hip and spine fractures are arguably the most important end point for osteoporotic fracture. Dr. McDougall suggests and this is confirmed to some degree by correspondence with Dr. Key that the younger, thinner and more highly active vegans may have had more injuries due to vigorous physical activity.

“The meta-analysis of protein intake on bone health by Darling et al published in AJCN in 2009 fails to find either benefit or a lack of benefit of protein on bone. If one approaches this study from the perspective of trying to understand the relationship between dietary patterns and bone, this result is not surprising. Again these researchers are trying to understand relationship of the single nutrient (this time) protein, in the context of widely varying dietary patterns. It makes sense then that any effect of this single nutrient might be obscured in a meta-analysis since other potentially important dietary factors likely also varied widely (fruit and vegetable intake, potassium, vitamin D, sodium, etc.).”

Dr. Lanou,

Thank you for your response. I appreciate your goal of helping humans, animals, and the environment.
I have a few more comments below.

Jack

“Hip and spine fractures are arguably the most important end point for osteoporotic fracture. Dr. McDougall suggests and this is confirmed to some degree by correspondence with Dr. Key that the younger, thinner and more highly active vegans may have had more injuries due to vigorous physical activity.”

It is interesting that the vegans did not have any hip fractures. However, the study did adjust for physical activity and age, so those differences should not explain much of the results. And to my knowledge, there is no reason to think that the lifestyles of the vegans getting more than 525 mg of calcium were any less active than the vegans getting less than 525 mg, yet those getting more than 525 mg did not have a higher fracture rate.

The cross-sectional studies on vegans’ bone health have, for the most part, not shown them to have better bone health than omnivores. Those studies are cited here.

Thus, to date, there is very little evidence that a vegan diet helps prevent osteoporosis.

I have not seen a study, that tracked calcium intake over time, that showed people with intakes of 500 mg or less have less fractures than those with higher intakes.

I realize that Dr. Lanou’s point is that we need to take a holistic approach to bone health and not focus on one nutrient. But even holistic approaches only affect bone on a molecular level; if there isn’t enough calcium to maintain bones, it doesn’t matter if the approach is holistic or not.

Because of the harm it causes cows, I very much want to see an end to the dairy industry. But it could harm cows and humans just as much if, at the same time, we tell them that it is not important to concern themselves with calcium. In my opinion, the evidence doesn’t justify taking this risk.

Thanks to the Vegetarian Society of Hawaii, you can now watch a video of my talk Vegan Nutrition: What Does the Science Say on-line. Click here.

A special thank you to Dr. William Harris for filming and putting the video together!

Hi, Jack. Have you ever heard about the role lutein, found in highest amounts in kale and spinach, plays in vision or eye health? I just watched a video (it’s 23, second from bottom on p.1) by Robyn Openshaw (the self-named Green Smoothie Girl) and she claims that she had really bad eyesight in college. Since then she’s had two to three handfuls of raw spinach a day (in smoothies) and she says that now her eyesight is 20/15. On another site, it says you’re supposed to cook the greens to release the lutein, so now I don’t know what to think.

Robyn Openshaw is misinformed about vitamin B12, saying in Part 2 of her GSG-SMOOTHIE 2.0 video that you can get it from brewer’s yeast, aloe vera, or a steak once every three years. Whether green smoothies improved her eyesight, I really have no idea. If they did, it could be any number of things in them, not just lutein.

All that said…Yes, lutein is thought to be good for protecting the eyes. I did a little research to see if lutein is better absorbed from cooked or uncooked spinach and it appears to be better absorbed from cooked, though the difference is not great according to this abstract.

It also appears that luetin is fat-soluble which should mean that eating some fat with foods high in lutein would increase its absorption. Fat soluble molecules are often better absorbed when cooked, but the one abstract above, the best one I could find, indicated that this is not the case for lutein.

The Fall 2009 issue of Vegetarian Voice magazine, the newsletter of the North American Vegetarian Society, has an article by Amy Joy Lanou and Michael Castleman, “A Whole Diet Approach to Building Better Bones.”

I will quote from the article to sum up their arguments:

“[W]e have known for at least 20 years that fracture rates are highest in areas where dairy and calcium consumption are also the highest.”

“Research shows that a low-acid diet, one that is high in fruits and vegetables and devoid of (or low in) animal protein (meats, poultry, fish, milk, eggs and cheese) helps keep calcium in bones.”

“[Osteoporosis is] actually a disease of calcium imbalance. Drinking milk and eating dairy foods provides calcium – but these foods are so high in protein that they draw more calcium out of bone then they replace.”

“We do need some calcium. The World Health Organization recommends 400 to 500 mg/day for people in countries at high risk of osteoporosis.”

“The best approach to osteoporosis prevention – the only one that makes scientific sense – is a diet very low in or devoid of animal foods and high in fruits and vegetables, combined with walking or equivalent exercise for 30 to 60 minutes a day, every day.”

If you have been following vegan nutrition advocacy for the past two decades, nothing above should be new to you. And here are the major problems I have with it:

1. Most non-vegans in Western countries get around 800 to 1200 mg of calcium per day. At this level of intake, I agree that there is little evidence that to prevent osteoporosis one needs even more calcium. However, Lanou and Castleman imply that all you need is a vegan diet containing 400 – 500 mg of calcium per day and walking for 30 to 60 minutes for strong bones. And they leave out the most important study published to date on bone health and vegans, a 2007 report from the EPIC-Oxford study which showed that vegans had a 30% higher rate of bone fractures than did meat-eaters and lacto-ovo vegetarians!

In that study, the vegans who got more than 525 mg of calcium had the same rate of bone fractures as the meat-eaters and lacto-ovo vegetarians, showing that vegans need more than 525 mg of calcium. (In the study, 32% of vegans had calcium intakes between 525 and 699 mg per day, and 24% had greater than 699 mg per day.)

This is the only study looking at the bone fracture rates of vegans.

2. Lanou and Castleman base most of their argument on the idea that animal protein leeches calcium from the bones. As I posted a few weeks ago, a meta-analysis looking at bone health and fractures found that “Overall, the weight of the evidence shows that the effect of dietary protein [including animal protein] on the skeleton appears to be favorable to a small extent or, at least, is not detrimental.”

In my opinion, the argument that a primary cause of osteoporosis is animal protein has always been on shaky ground.

3. Lanou and Castleman leave vitamin D out of their final recommendations (they briefly mention you can get it from the sun earlier in the article). Vitamin D can be a significant problem for many vegans and needs to be addressed in discussions of bone health.

4. I do not see why it is necessary to make an argument that people only need 400 to 500 mg of calcium per day, when the evidence is so lacking (and actually points in the other direction). What harm could come from encouraging vegans to get at least the low end of what is a normal amount of calcium (like 700 to 800 mg/day) in Western countries? None. But what harm could come from vegans not getting that much? Only osteoporosis!

In summary, there is no direct evidence that a vegan diet with only 400 to 500 mg of calcium per day prevents osteoporosis. The direct evidence is just the opposite.

More info on vegan diets and bone health.

A meta-analysis looking at protein intake and bone health was published this month in the American Journal of Clinical Nutrition (1).

In terms of bone mineral density (BMD), the authors reported:

“Overall, there was very little evidence of a deleterious influence of protein intake on BMD, with most cross-sectional surveys and cohort studies reporting either no influence or a positive influence. Thus, 15 cross-sectional surveys found a statistically significant positive relation between protein intake and at least one BMD site. However, 18 studies found no significant correlation between protein intake and at least one BMD site.

“The cohort studies also identified little evidence of any deleterious influence of protein intake on bone. … [N]o studies showed a significant increase in BMD loss with increased protein intake, and only one study showed a significant decrease in BMD loss with increased animal and total protein intakes.”

In terms of bone fracture rates, the authors reported:

“Overall, the [seven] cohort studies indicated either a benefit or no effect of protein intake on hip fracture relative risk, with only one study reporting a significant increase in risk with increasing animal protein intake and increasing animal to vegetable protein ratio. Three studies found a decreased relative risk of hip fracture with increasing animal, total, and vegetable protein intakes. Two studies found no significant association of animal protein with fracture risk, whereas 2 studies found no association of total protein with fracture risk. Last, 2 studies found no relation between fracture risk and vegetable protein.”

In summary:

“Overall, the weight of the evidence shows that the effect of dietary protein on the skeleton appears to be favorable to a small extent or, at least, is not detrimental. However, the long-term clinical importance of the effect is unclear, and a reduction in fracture risk was not seen. More research is required to resolve the protein debate. In the meantime the protein intakes and balance of different protein sources as indicated in the current healthy eating guidelines represent appropriate dietary advice.”

Reference

1. Darling AL, Millward DJ, Torgerson DJ, Hewitt CE, Lanham-New SA. Dietary protein and bone health: a systematic review and meta-analysis. Am J Clin Nutr. 2009 Dec;90(6):1674-92. Epub 2009 Nov 4.

After my post about Leaky Gut Syndrome, I had an interesting exchange with a reader:

“Did you, by any chance, read this article in the August issue of Scientific American, concerning celiac disease and leaky gut?

“Later in the article, it is mentioned that the medical profession had treated the concept of leaky gut with skepticism, but now it is known that there is such a thing, and how zonulin can change the permeability of the small intestine.

“Concerning my own history, which may be relevant, I have a long history of inhalant and food allergies; took allergy shots for 40 years. Since 9 months ago, when my doctor put me on the following regimen, I have been virtually allergy free for the first time in memory, not only to foods, but to inhalants like pollen, dust, mold, etc., and was able to quit the allergy shots – which weren’t doing that much good anyway. Also, I have not experienced any asthma attacks during the past 9 months (which is unusual). My whole life has been spent with a Kleenex in hand because of a constant nasal drip, but not anymore!

“The regimen is prescription enzymes, Pancrelipase 20000 3 x day, plus HCL (650 mg) with every meal (3 to 5 caps depending on size of meal). You start out with 1 HCL and then work up gradually to determine your limit because you don’t want to overdose and burn your stomach. Unfortunately, the enzymes are not vegan. [Note: “Pancrelipase” sounds like it would only digest fat, but it also contains enzymes to digest protein and carbohydrate.]

“The whole point I find interesting is how my chronic allergies could be so tied to poor digestion, and possibly a leaky gut – which I was told I had by alternative therapists in the 60’s and 70’s. The “real” docs just put me on allergy shots.

“Also, my main food allergies were dairy and eggs (found by RAST test done by “real” doctor) and were making me constantly ill, so I gave them up. It was so easy to become vegan after that.

“It’s a shame about the animal source enzymes, probably the only non-vegan thing I’m doing though – except for feeding my cats meat (yuck!).

“One other thing about the enzymes and HCL: For a long time I thought I was gluten intolerant because of digestive problems (bloating, gas) whenever I ate wheat. Now, gluten products don’t bother me at all! So I wonder if a lot of the gluten intolerance craze is really a problem with poor digestion?

“The HCL alone works for digestion, but the digestive enzymes seem to be crucial in reducing allergic inflammation, like stuffy sinuses, asthma, runny nose, etc. None of the plant enzymes I have tried are as powerful.

“I started taking the prescription pancreatic enzymes 1 week before I started the HCL regimen. My head cleared up immediately upon taking the first enzyme capsule, and stayed clear, with no more nasal drip. It appears that I no longer have any inhalant allergies. I feel wonderful and more energetic because I can finally breathe. I’ve had no asthma or any other allergic symptoms during this time. It’s unbelievable considering my vast allergy history.

“All the plant enzymes I have tried before would cause my head to clear up for just a minute or two on a few occasions, but did not have lasting effects on my usual allergies. I have not yet experimented with megadoses of plant enzymes, however – so that might be something to try in the future.

“I was shocked to find that I can take as many as 7 HCL capsules during a large meal with no burning at all! That must mean I produce almost no HCL. My husband, on the other hand, experiences burning with even 1 capsule – so his HCL level is apparently normal. It’s very important to start with only 1 capsule and then work up, because you could do some serious damage with HCL. [Note to readers: You should only use HCL under the guidance of a physician.]

“Since being on both of these supplements, I seem to be digesting everything better and no longer worry about gluten or any other foods except [a couple brands of soy ice cream].

“Unfortunately, here is another glitch. I take Solaray Betaine HCL with Pepsin 650 mg. From what I can tell, the pepsin is not vegan either – darn! I don’t know if the HCL alone (if you can find it) would be as effective. More and more, I like VO’s stated philosophy of not sweating small non-vegan ingredients. Surely, if we are all vegan in the future, pancreatic enzymes, lipase, and pepsin will be able to be humanely synthesized.”

—-

The article referred to above from Scientific American suggests that many autoimmune disorders might be triggered by an underlying case of celiac disease and/or a leaky gut. Celiac disease is an autoimmune disorder triggered by eating gluten and related proteins in some grains. The article says that about 1% of people have celiac disease, although most do not know it.

Zonulin is a protein that is released by intestinal cells and causes the gaps between intestinal cells to be more permeable and allow undigested proteins to seep through, where an immune response will be mounted against them. Many people with autoimmune diseases have unusually high levels of zonulin and high intestinal permeability. In cases of celiac disease, gluten causes an increase in zonulin.

Alvine Pharmaceuticals is in the process of creating digestive enzymes that break down gluten fragments that are normally resistant to digestion. I do not know if they could be considered vegan.

The author of the Scientific American article, Alessio Fasano, co-founded Alba Therapeutics which is working on a drug, Larazotide, that inhibits zonulin. They are currently conducting clinical trials.

This is an interesting article from New Scientist about some companies that are working on producing EPA, DHA, and STA in plants:

US FDA says omega-3 oils from GM soya are safe to eat

Excerpt:

“BASF has inserted five genes from algae that naturally make EPA and DHA into the canola genome. Its product is still in development.

“Monsanto has taken a different approach. It inserted two genes into the soybean genome, one from a plant related to primrose and one from a fungus. The modified soybean produces stearidonic acid, or SDA. Like ALA, SDA is converted into EPA in the body, but in much higher proportions….”