New Study Answers Questions about the Vegan Diet, Calcium, and Bones

[Guest guest]

> 3a. Re: New Study Answers Questions about the Vegan Diet, Calcium, and B

> Posted by: " Karen " karen karen_

> Mon Mar 26, 2007 2:41 pm (PST)

> Last month, a study was cited on this list about vegans having more

> fractures than meat eaters and possible reasons that might occur.

> Dr. McDougall has addressed that study in this month's McDougall

> Newsletter, and I think his comments make a lot of sense. He

> exchanged messages with one of the authors of the article, and I

> found those exchanges very informative, as well.

>

[snip]

 

> To read the entire article (I recommend it), use this link:

>

> http://www.drmcdougall.com/misc/2007nl/mar/defend.htm

 

I'm the person who originally posted an article on BAV describing the

results of the EPIC-Oxford study on bone fractures in vegans, to which Karen

was responding. You can see the original article here:

 

http://www.veganhealth.org/articles/bones

 

 

 

In their correspondence linked from the post above, Dr. Timothy Key of

EPIC-Oxford says to Dr. McDougall, " We don't think that our results should

be taken as an argument to eat dairy products; simply that vegans do need to

eat enough calcium. Would you agree with the UK EAR of 525 mg/d as a

reasonable minimum? " In his article, Dr. McDougall doesn't provide an answer

as to whether he agrees.

 

 

 

In my opinion, 525 mg of calcium is not that much calcium. For most vegans

not meeting that much, it would mean simply drinking a glass of fortified

soymilk each day. You could also eat more greens and get additional

calcium - but you have to do it, you can't just rest assured knowing that

greens have a lot of calcium without eating them every day.

 

 

 

Even if the bone fracture study is wrong, adding 200 - 300 mg of calcium a

day to an otherwise unfortified diet is very unlikely to do any harm. Vegans

would still be below the U.S. Dietary Reference Intake.

 

 

 

Dr. McDougall says, " The reason I believe this study found more fractures in

the vegan group is these healthier, younger people were far more active and

as a result sustained more injuries. Their increased physical activity

leading to more fractures is noted by the fact that they were on average 11

years younger, were less fat (lower BMI), and were reported to walk, cycle

and do other vigorous activities more than the meat, fish, and dairy

groups. " As Dr. Key pointed out, the researchers tried to adjust the

results for those factors. That's the best you can do - try to adjust for

confounding variables.

 

 

 

Dr. McDougall says, " [T]he authors of this study conclude calcium is the

problem and this is based on findings in only 74 people with fractures

following a vegan diet. " Duly noted. But this is the *only* study of vegans

and bone fractures and it required thousands of participants and an enormous

amount of work and time. Given that the results of the only study on bone

fractures in vegans has resulted in higher fracture rates in vegans with

calcium levels lower than 525 mg, it's something we might want to pay

attention to. I'm just glad some people actually took the time and money to

do such a study rather than for us to continue moving forward without any

data on vegans.

 

 

 

If you are vegan for animals, it seems vital to err on the side of caution

so that others will view the vegan diet as healthy. It's a good thing enough

vegans in the EPIC-Oxford study were getting more than 525 mg of calcium per

day that there was a subset of vegans that had the same fracture rates as

non-vegans (assuming calcium was the issue which, until proven otherwise, is

the safest assumption, in my opinion).

 

 

 

Dr. McDougall continues, " You should be asking, how could such meager and

contradictory evidence be so influential? " Dr. Key points out, " [T]he

optimal intake of calcium for preventing fractures has been controversial

and the evidence is somewhat conflicting. " That means there is evidence on

*both* sides. As someone who has followed a lot of the evidence over the

years, I wasn't surprised when I heard the results of this study. Indeed, it

was a relief to think that vegans probably don't have to get much more than

525 mg per day.

 

 

 

I hope to get time to write an article detailing more of the contradictory

evidence. For now, the most comprehensive study I've found on a related

issue (dairy and bone fractures) is here:

 

http://tinyurl.com/2b6l9j .

 

 

 

Sincerely,

 

 

 

Jack Norris, Registered Dietitian

Vegan Outreach

www.veganoutreach.org