Confusion about vegans and life expectancy

[adam.rurka]

I'm really confused about being a vegan and living longer. It obviously seems to reduce your chance of nearly every type of cancer by quite a bit, as well as heart disease by quite a bit, but I was reading some research that said vegans don't actually live longer.

I'm not sure who to trust. How can vegans not live longer despite having better blood pressure, cholesterol, fewer bone fractures, higher anti-oxidant intake, etc..?!

Is it that they live the same but have more disease free years?
Is the data wrong? Do vegans live longer?
Is there not enough research in the area?
If vegans aren't dying of heart disease and cancer, then what does kill them?

(BTW, 5 month vegetarian, 1 month vegan here - loving everything about it too)

[DiaShel]

Sorry, I don't know for sure. Everything I ever read said that vegans do live longer, about 10 years, but the never said how the research is done. I have a hard time believing that vegans don't live any longer as I have read reports based on research that there is lower risk of heart disease, diabetes, cancer, obesity, etc, etc. I think lifespan would be quite difficult to research. There are a lot of variables. How long was the person vegan, vegan diets can vary dramatically (as can any), genetic factors, etc. Then of course, a vegan can just as easily be hit by a truck ;) You would need a very large subject pool because of the variables and I don't know if there are enough vegans of an elderly age to do it! I think they'll be able to do it in maybe 20 plus years when vegans start dying of old age, but I don't think many people of that sort of age are vegan because it wasn't much heard of 50 years ago.

[Johnstuff]

I've also heard that cyclists live 10 years longer too...so I'm hoping to make 103 at least :lol:

I doubt there's enough data on vegans for them to say for sure. I guess 'The China Study' is probably the best place to start?

You mention antioxidants, do you know of any research that says they are actually beneficial?

[harpy]

The research you've heard about may be the same as is mentioned in this article - which implies that overall life expectancy is the same as that of regular meat-eaters but not quite so good as occasional meat-eaters, vegetarians etc

http://www.scienzavegetariana.it/rubriche/cong2002/vegcon_B12_en.html

I haven't looked into the quality of the original research but the references are given at the end if you would like to follow it up yourself. I tend to agree with the others that there probably aren't, or haven't been, enough vegans to produce reliable results.

You'll see that the author thinks vegan life expectancy may be affected by homocysteine issues, but the article is not new and I gather this idea is controversial - if you search this forum for "homocysteine" you should find some discussion of it.

Personally I'm not vegan for my health. On the other hand, I wouldn't do it if I thought it was going to kill me prematurely but I don't see any evidence that it will. Of course it's probably a good idea to pay attention to certain nutrient requirements, vitamins B12 and D for example. The same goes for omnivores of course - they can't assume they will get all the nutrients they need without thinking about it.

[Korn]

There's an article about meat and life expectancy here:
http://www.ajcn.org/content/78/3/526S.full

AFAIK there's not enough info on life expectancy among lifelong vegans. And both because there's no such thing as one vegan diet, it's hard to tell what a balanced, varied diet will in terms of life expectancy... Some people who eat vegan started to do so because they had health problems, and may therefore be part of a study on vegans and health/life expectancy. Many who go vegan for ethical reasons may unfortunately also have low focus on health and nutrition - and they may also be part of existing studies.

The Vegan Society has a book which contains a table showing the death risk difference between vegans and meat eaters who don't eat as much meat as the general population. There was no difference. The conclusion of that book is that the vegans studied were living about 5 years longer than their typical meat-eating counterparts, and that they could "do even better with adequate vitamin B12". The book also suggested that higher B12 levels/better homocysteine levels in US vegans compared with UK vegans was due to the fact that it's more common to use multivitamins in US.

Occasional meat eaters, lacto-vegetarians and fish eaters may have higher B12, and therefore lower homocysteine levels than vegans not supplementing with B12, for this reason:

• Vegans in a 'modern' society are exposed to various B12 'killers', but so if they don't take compensate for this by take a B12 supplement, their B12 levels will end up too low.

• Meat eaters in the same modern society are also exposed to various B12 killers, but they also eat meat/dairy etc from (plant eating) animals, which often (at least to some degree) compensates for the 'unnaturally' low B12 - but also includes a risk of other side effects of high B12 intake (and risk of getting very high B12 levels associated with certain health problems).

A table in the above mentioned book ('Plant Based Nutrition and Health - Stephen Walsh, PhD) shows that most of the relevant studies have found that vegans have higher homocysteine levels than vegans. The book also mentions that the rise in homocysteine does not occur in 'those vegans ensuring adequate B12 intake of 3 mcg or more per day".

[harpy]

Yes, the article I posted a link to above is by the author of "Plant Based Nutrition and Health" and I think the mortality table in it may be the same one that appears there.

[Korn]

His theory seems interesting when seen isolated from all other studies on homocysteine and B12, but I agree with those who think that more studies are needed before one can come to any firm conclusions about B12 and homocysteine (as discussed here (http://www.veganforum.com/forums/showthread.php?108-B12-homocysteine-amp-heart-disease)). And even if it can be properly documented that increased B12 used to normalize homocysteine levels may have no real effect on life expectancy for most people - increased B12 will be good in terms of life expectancy for those with very low B12.

[harpy]

Yes, from what I can gather there is a range of evidence that very low vitamin B12 could be problematic in various ways, but it seems difficult to say much more than that with confidence at present.

(Guess I should have asked the doc for more details of my B12 level in addition to the fact that it was "fine" eh? Perhaps I'll phone them up and see if they've lost it yet :) )

[adam.rurka]

Hmm. Well, speaking of B-12, my multi-vitamin/mineral has 100mcg in each tablet. This seems like a lot?

[Risker]

Hmm. Well, speaking of B-12, my multi-vitamin/mineral has 100mcg in each tablet. This seems like a lot?

I'd say that's about right, the bioavailability of b12 supplements can be as low as 5% and it's pretty much impossible to take too much as it's water soluble so any that your body doesn't use is expelled via urination. Personally I take 500mcg tabs.

I try not to worry too much about life expectancy because it reduces your life expectancy.

[adam.rurka]

^ Ha! True!