Vitamin B12 and Natural Herbivores

[Guest guest]

Karen wrote:

 

> Mr. Norris' statements started me thinking about whether the need for

B12 is what distinguishes herbivores from omnivores. I wonder if the

other large herbivores (elephants, cows...) need B12, and if so,

where they get it. I always thought they got it from the soil on the

plants they eat, but I'm no expert on that.

 

Here is an explanation of how some other herbivores get B12:

 

http://www.veganhealth.org/b12/animal

 

For those who don't want to go to the link, I can sum it up by saying that

they have bacteria in their digestive tracts that produce B12 and/or they

eat feces.

 

There are two basic theories about how humans could be herbivores and still

get vitamin B12.

 

One says that there is vitamin B12-producing bacteria in the soil (some

evidence of this, but not enough -- it also would rely on there being cobalt

in the soil which is needed for bacteria to produce B12 and some soil does

not have enough cobalt) and in fecal material (lots of evidence), and that

food and water used to be contaminated with this bacteria. Now that we live

in a clean society, we don't have the benefit of this bacteria and thus get

B12 deficient.

 

Even if true, I am very skeptical that this could produce enough vitamin B12

for humans to live. I base this mostly on the fact that many vegan women who

do not supplement with vitamin B12 have infants who get severely deficient

(because they are born with very low levels and then their mother's breast

milk provides very little) and some even have died. I do not see how

bacterial contamination in ancient times could provide enough B12 to reverse

this phenomena.

 

The second theory says that in more of a state of nature, bacteria in our

intestines produce vitamin B12 but that we kill off the bacteria from our

lifestyle and particularly from taking antibiotics. It's an interesting

theory but unlikely in my opinion.

 

While the simplest explanation might not always be the right one, it

normally is, and I think it is probably the best way to check one's beliefs

against reality. The two theories above are just a lot more complicated than

the simple explanation of how humans have received B12 in the past -- they

got it from animal products. There is already a great deal of evidence to

back up this simpler theory.

 

By the way, vitamin B12 isn't why I think humans are natural omnivores. I

think it because there is a lot of evidence that we have eaten animal

products and/or meat throughout our history. It's just that the vitamin B12

issue makes it nearly impossible for us to have been complete herbivores

throughout our history, unless we were to eat our feces (which we might have

done or could have done if necessary, though it seems immensely unappealing

to me now).

 

If your perspective is that a vegan diet is quite easy to adhere to and that

it cures just about everyone of anything that ails them, then I can see how

the " simplest explanation " is that we are true herbivores. And how I wish it

were true. I do think a vegan diet can help protect against heart disease

and some other disease compared to the standard American diet, but I don't

agree that a vegan diet is far and away a better diet than all others.

 

I will end with a quote I like by Tom Billings:

 

" You really don't need the naturalness claim to be a veg*n! That is,

moral/spiritual reasons alone are adequate to justify following a veg*n diet

(assuming the diet works for you, of course). Further, if the motivation for

your diet is moral and/or spiritual, then you will want the basis of your

diet to be honest as well as compassionate. In that case, ditching the false

myths of naturalness presents no problems; indeed, ditching false myths

means that you are ditching a burden. "

 

Of course, if you really believe that humans are naturally vegan, then you

don't have a burden to ditch.

 

Jack Norris, Registered Dietitian

Vegan Outreach

California Office: 916-375-0014