Discussion Board

In July 2009 the ADA published a position paper on Vegetarian Diets:

http://www.eatright.org/HealthProfessio ... px?id=7204

Do you have any comments on the content of this position paper - where they got it right or areas where they did not?

I posted the paper here in the forum when it first came out..

viewtopic.php?f=22&t=12102

In general, I think it is a well down paper and will refer people to it.

If you have any specifics you want to discuss, I would be glad too.

Let me know.

In Health
Jeff

I was a little surprised about the sections on Calcium and Osteoporosis, given that world-wide studies show the highest rates of hip fractures in the countries consuming the most meat and dairy. While acknowledging a limited amount of data on the bone health of vegans, the ADA paper indicated that the bone density of vegans was lower than in non-vegetarians and that "vegans had a 30% higher risk of fracture possibly due to their considerably lower mean calcium intake."

There are so few life-long vegans in the West it would seem hard to draw conclusions. How long does someone have to be on a vegan diet before they are considered 'vegan'? Does the length of time someone is on a vegan diet affect their ability to absorb calcium? Are vegans at risk for a period of time (months, years?) for the absorption of calcium, while their body adjusts to lower intake levels?

We also know that vitamin D plays an important role in all this, so the data would have to be normalized for exposure to sunlight and dietary intake of vitamin D. Is the data adjusted for physical activity that tends to strengthen bones? And the measures themselves - are they really reflective of bone health?

I have searched for bone fracture data for China, including the Cornell-Oxford-China site (http://www.ctsu.ox.ac.uk/~china/monograph/) but have not found data on this. China is one of the few places in the world where dairy is not part of the traditional diet for much of the country - so there is a good chance of finding people close to near vegan diets - especially in rural China. The following article about T Colin Campbell's China Study leads me to believe that vegans ought to have greater bone densities rather than lower ones:

http://www.news.cornell.edu/Chronicle/9 ... rosis.html

In any case, the ADA position paper has left me confused on these issues.

These are all epidemiological studies and while they provide interesting information and possible relationships, they can not prove causation. As there are so many factors that contribute to osteoporosis, causation must be proved in studies which control for all the other contributing factors.



I don't see them "drawing hard conclusions." I see both you and them making similar comments about limited data, limited population & only a possible relationship.



All of these are good questions and why epidemiological studies can not be used to prove anything but only show possible relationships. In addition, all of these questions can, and should be asked of the same data you first mentioned.



Remember, studies on vegans, like the Klaper Study, while interesting, do not really apply here. The reason is that there are so many vegan diets and so many different lifestyles of those who follow vegan diets, that I don't see how any hard conclusions can be made from any study on any "vegan" group.

Veganism does not automatically equate to a healthy diet and/or lifestyle and my personal experience over 3 decades, is that most vegans I have encountered do not follow a healthy diet and lifestyle. I have not seen this improving in recent times, either.

While many in these forums choose to be vegan, the McDougall program is about a healthy diet and lifestyle, vegan or not.

I do not see how a study (or studies) on vegans, who in general are not following any specific guidelines and/or recommendations other than to avoid animal products, applies in anyway at all to followers of the McDougall program (or similar plant-based healthy diet) who are following specific guidelines and principles of a health supporting diet and lifestyle.

My recommendation, which I have made to most all the vegan researchers, is that the word "vegan" should never be used in a published study to describe a population/group without clear definitions or descriptions of exactly how they live and what they eat. Coca Cola and French fry eating vegans will do nothing to help promote the benefits of a healthy plant based diet and so vegans who choose to eat poorly must be identified and grouped separately in any vegan study. Then, we will be able to see what benefit are attributed to eating a healthy plant based (but not exclusive) diet, and what benefits, if any, are attributed to the "vegan" part.

And, to be really fair, we would have to hold the "vegan" studies to the same degree of quality, standards, scrutiny and even criticism, that we do the non vegan studies.

In Health
Jeff

So maybe we should call vegans who follow the McDougall healthy diet and lifestyle principles 'McVegans'?

Great idea!!



In Health
Jeff

Interesting, insightful discussion. Another factor that complicates this is that weight bearing strengthens bones. So if one is heavier from eating eating a SAD, he will stress and strengthen the bones more when he stands, walks etc. However, if one is heavier...he needs stronger bones to support his weight. So it seems to me that all of these factors mentioned here make it very difficult to draw any solid conclusions about a generic vegetarian diet
versus the SAD.

We also know it would be very difficult to find human volunteers who would cooperate as well as mice and other small mammals in regard to researching this.

I think, however, that the McVegans (I like that!) will (over time) have fewer bone problems and other health problems than those who follow the SAD or a generic vegetarian diet. By generic vegetarian diet, I mean one that is higher in fat and calories and lower in essential nutrients than the McVegan's diet. There is enough evidence at this site to convince me!