Author: Jack Norris RD

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.”

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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….”

Here is an email exchange I recently had:

November 06, 2009

Hi Jack,

I’ve been vegan for almost two years and am wondering about a skin condition I recently developed. I have a red flaky patch of skin right below the corner of my lip and above both eyelids. The patch is not itchy or yellowish, so I suspect it is not eczema. I am wondering if the patches are the result of a vitamin deficiency. I used to take a multivitamin, but I quit taking it because my skin took on a yellowish hue, especially in the winter when I eat more squash (and my doctor thought I might be getting too much beta-carotene). I now only take a B-complex vitamin. Is it possible that the skin patches are a sign that I’m not getting enough of a particular vitamin?

My response:

A lack of vitamin D can cause psoriasis in some cases, but other than D and B-vitamins, which it sounds like you are good on, I don’t know what it might be or if it is likely to be nutrition-related. It’s definitely not a common complaint I hear from people who are vegan.

November 14, 2009

Dear Jack,

I saw my primary care doctor this week and she speculated that I might have a vitamin D deficiency. I began taking supplements and going outside for 30 minutes a day around noon. The patches have all but disappeared in a matter of days. Just wanted to let you know in case you ever come across any other individuals with the same condition. I have since read more about the health problems associated with vitamin D deficiency, and I am thankful my deficiency manifested itself in a way that I was able to take notice and do something about it.

Addendum Nov 15, sent from a different reader:

I had ‘eczema’ for years every winter and when I started taking Vitamin D2, 2000 IU, it went away for good. I also had my 25-hydroxy-Vitamin D level tested and it was at the very lowest end of normal…. Any skin condition that’s worse in the winter (where UV is low in the winter) I would suspect Vitamin D deficiency.

A study was just published showing that Chinese women living in Singapore who ate more soy had a reduced risk of hip fractures. Compared with women in the lowest one-fourth of intakes for tofu, soy protein, and isoflavones, those in all three of the higher intake categories had a 21%–36% reduction in risk. Soy did not show any benefit for men.

Koh WP, Wu AH, Wang R, Ang LW, Heng D, Yuan JM, Yu MC. Gender-specific associations between soy and risk of hip fracture in the Singapore Chinese Health Study. Am J Epidemiol. 2009 Oct 1;170(7):901-9. Epub 2009 Aug 31.

I was corresponding with JoAnn Farb who told me something interesting she has noticed about carrot juice protecting against sunburn:

“I discovered on several occasions that drinking large amounts of carrot juice and/or to a lesser extent — simply eating huge amounts of raw greens, reduces any observable changes in skin color (burning or tanning) when exposed to sun.

“I first noticed this on a canoe trip — years ago — I should have burned — was not using sunscreen and everyone else who didn’t use it did burn badly. But I had been drinking lots of carrot juice every day before hand. Then again in Australia, in January, in Sydney on the beach, Sarina [her daughter] was one year old at the time and pretty much nursing for all her calories. Each day over the noon hour I took her to the beach and let her crawl around naked — and I was in a swim suit. At first I just did ten minutes and then we put full clothing on. Each day I saw no burn and no tan. I increased the time more — until we were fully exposed for well over an hour and saw absolutely no reactions on our skin. There were juice bars everywhere; I was drinking two to three large glasses of fresh carrot juice every day.

“I have certainly had my share of sunburns at other times, from much less exposure, but have tested this repeatedly. Not only will carrot juice protect me and my family from sunburns, but if we have not been drinking carrot juice and do happen to burn, we will drink large amounts right away and the burn fades quickly.”

I have long known about the orange tint that people who drink a lot of carrot juice can get, but I was not aware of any sunburn protection. I checked it out and found research showing that beta-carotene does protect against sunburn:

Köpcke W, Krutmann J. Protection from sunburn with beta-Carotene — a meta-analysis. Photochem Photobiol. 2008 Mar-Apr;84(2):284-8. Epub 2007 Dec 15.

The study found that taking beta-carotene for 10 weeks, in amounts of about 57 mg per day, protected against sunburn. One cup of carrot juice has about 22 mg of beta-carotene.

The researchers said the SPF of beta-carotene was about 4. They thought the benefit from beta-carotene could be due to its antioxidant potential or interference in other parts of the biochemical pathways leading to sunburn.

JoAnn went on to ask:

“I have always wondered, since Michael Hollick mentions the pinking of the skin as a way to get an indication of how much vitamin D one is potentially making, does consuming all this carrot juice in some way inhibit vitamin D production? Or is the pinking of the skin merely a general way to gauge melanin amounts but otherwise not really related to biosynthesis of D?”

I’m afraid I do not know the answer to this and I could not find any research on it. I did, however, find one study in which higher intakes of beta-carotene were associated with less bone mineral loss in the elderly:

Sahni S, Hannan MT, Blumberg J, Cupples LA, Kiel DP, Tucker KL. Inverse association of carotenoid intakes with 4-y change in bone mineral density in elderly men and women: the Framingham osteoporosis Study. Am J Clin Nutr. 2009 Jan;89(1):416-24. Epub 2008 Dec 3.

It appears that in this case, beta-carotene was not noticeably interfering with any vitamin D formation in these people, though this is a very indirect way to try to answer that question.

Every month or so, someone reads my recommendations for vegans, checks out some vegan multivitamins, and then writes me asking about the high levels (many times the RDA) of some individual vitamins in many of the vegan multivitamins.

While I’m not aware that taking B vitamins and vitamin C in the amounts found in typical vegan multis poses any sort of health problem, I thought it might interest readers to hear what supplements I take.

For vitamin B12 and calcium, I drink about 1 to 1.5 glasses of fortified soymilk each day. In the past, I have taken a Trader Joe’s 500 mg calcium / 250 mg magnesium/ 7.5 zinc supplement on days I didn’t drink enough soymilk; but lately I’ve been taking it every day. I also take a 1,000 mcg B12 supplement about once a week.

For vitamin D, I try to sit out in the sun for 20 minutes each day (10 minutes facing the sun, 10 minutes facing away). I save any reading that I can do away from the computer for this time each day. I normally get a lot of sun on the weekends. During the dead of winter, I have a vitamin D lamp that I sit in front of for about 10 minutes a day. Vitamin D2 supplements should be fine – I don’t think every vegan needs to run out and get a vitamin D lamp for the winter. I tend to suffer from (self-diagnosed) seasonal affective disorder, so I like the lamp. Until a year ago, I was living in Sacramento where there was plenty of sun throughout the year, but now that I live in Oakland, which can be a lot more cloudy, I have found that I need more light during the winter.

For iodine, I take a 225 mcg supplement every few days. I pop one when I realize that I haven’t in awhile.

For omega-3s, I am a bit of an anomaly, and do not strictly adhere to my own recommendations. Around 2002, I had my prothrombin time tested just to see where it was. Prothrombin time is a measure of how fast your blood clots. Being a vegan, I wanted to make sure I was getting enough omega-3 and that my blood wasn’t clotting too fast. Well, it turned out that it was actually clotting too slowly (but not by much). I had been taking 1 tsp of flaxseed per day for some time (a couple years). I’m not sure if that was related, but I decided to stop supplementing as omega-3s slow blood-clotting time. I have had my prothrombin time tested a few times since then and it is always just a tiny bit slower than normal. So for omega-3s, I will take a DHA tablet once in awhile, but by no means on a daily basis as I recommend for other vegans. I do eat canola oil regularly, which has omega-3s, but not nearly as much as flaxseed oil.

I drink about 4 oz of carrot juice a day to make sure I’m getting beta-carotene.

And that’s it. I hope I haven’t raised more questions than I’ve answered!

Leaky gut syndrome is a phenomenon that may, or may not, actually exist. The theory is that things (such as antibiotics, infections, and inflammation) can damage the cells that line the intestines and weaken the “tight junctions” between the cells. This causes there to be small gaps between the cells and, thus, particles that the cells would normally prevent from entering the bloodstream get through. This, in turn, causes the body to mount an immune reaction against these particles which are viewed as foreign invaders.

A leaky gut has been implicated by various nutritionists as one of the causes of chronic fatigue syndrome — another syndrome about which little is known with certainty.

Wikipedia.org has a concise explanation of leaky gut syndrome. Most interest has been about its relation to autism, but that is not my focus here.

It is my own personal theory that allergy tests that measure immunoglobulin G (IgG), and find that someone is “allergic” to a host of different foods, are sometimes merely uncovering a leaky gut in someone who is not actually allergic to all or most of those foods.

So what does the research say? Not much. There has been very little published on leaky gut syndrome. I could find only one clinical trial (1).

The purpose of this trial was to see if they could get immunoglobulin A (IgA) and M (IgM) levels to go down in people with chronic fatigue syndrome. To do this, they used a dietary regimen, but their purpose was not to actually test this regimen, and they, therefore, give very few details about it; they merely say:

“All patients followed the leaky gut diet and took glutamine, zinc and [N-acetyl-L-cysteine], in combination with other [natural anti-inflammatory and antioxidative substances], which were given according to the immune and biochemical status of the patients, i.e. L-carnitine, coenzyme Q10, taurine and lipoic acid (in case of carnitine and/or coenzyme Q10 shortage); or curcumine and quercitine (in case of systemic or intracellular inflammation).”

They described their “leaky gut diet” as a dairy and gluten-free, low-carbohydrate diet.

Their study found that some people’s IgA and IgM levels were reduced on this regimen. They also found that a younger age at onset of chronic fatigue, a shorter duration of illness, and a younger age of the patient led to a better outcome.

It’s important to note that there was no control group and so it could be that patients were merely responding to the care and attention they were receiving or from a placebo effect.

This blog post is just to get something started on the subject. As more research comes out, I will post updates.

Reference

1. Maes M, Leunis JC. Normalization of leaky gut in chronic fatigue syndrome (CFS) is accompanied by a clinical improvement: effects of age, duration of illness and the translocation of LPS from gram-negative bacteria. Neuro Endocrinol Lett. 2008 Dec;29(6):902-10.