Vitamin D: Does the Source Matter?

[Guest guest]

Vitamin D: Does the Source Matter?

 

Vitamin D: Does the Source Matter? JoAnn Guest Jun

27, 2005 19:24

PDT

http://www.willner.com/article.aspx?artid=43

 

Vitamin D--Does the Source Matter?

The following is an excerpt from The Willner Window

radio program,

which

can be heard every Sunday on WOR (710 AM) from 2 to 4

pm, or over the

internet at www.wor710.com.

 

Arnie: Good afternoon everyone, this is .... Welcome

to The Willner

Window. For those of you who might be first-time

listeners, the focus

of

this show is nutritional supplements–vitamins, herbs,

homeopathic

remedies–and their proper usage. With me this

afternoon is . . We are

going to start off the program today with some

information on vitamin

D.

 

 

Don: Vitamin D has been receiving a lot of attention

lately. As most of

you know, vitamin D is required for our body to

properly utilize

calcium

in the formation of bone. In addition, we now see a

lot of research

that

it may play a role in reducing certain types of

cancer, such as breast

cancer and colon cancer.

 

The body can make its own vitamin D, when sunlight

interacts with the

skin. In addition, you can get it from food, or

supplements.

As some of you know, there are two types of vitamin D

used in foods and

supplements, vitamin D2 and vitamin D3.

 

Arnie: We explain the differences between the two in

our book, The Best

Supplements For Your Health. Vitamin D2 is identified

as

“ergocalciferol” and vitamin D3 is identified as

“cholecalciferol.”

 

D2 is derived from plant sources, and D3 is derived

from animal

sources.

For this reason, vegetarians have sometimes expressed

as preference for

vitamin D2. The vitamin D3 form is most widely used,

however.

 

Dr. Podell: But there may be other differences. In

findings recently

presented by researchers from Creighton University in

Omaha, shows that

there is significantly greater potency in the D3 form

over the D2 form.

 

This is important because research now indicates that

more people are

actually deficient in vitamin D than was previously

thought to be the

case. Warnings to pregnant women and children has been

issued, for

example, advising them to take vitamin D supplements

to prevent a

resurgence of rickets.

 

There is concern that the increased use of sun

protection creams might

be reducing the amount of vitamin D produced in the

skin.

 

Arnie: The study involved giving a large dose, 50,000

IU’s, of one form

of vitamin D or the other, randomly, to 20 healthy

male volunteers.

Over

a period of 28 days, blood levels of vitamin D and its

product

25-hydroxyvitamin D were measured.

 

The two calciferols produced similar rises in serum

concentration of

the

native vitamin, indicating equivalent absorption. Both

forms of vitamin

D produced similar initial rises in serum 25

hydroxyvitamin D over the

first three days.

 

But serum 25 hydroxyvitamin D fell rapidly in the

vitamin D2 treated

subjects and was not different from baseline at 14

days.

Meanwhile 25 hydroxyvitamin D continued to rise in the

D3 treated

subjects, peaking by 14 days and continuing to remain

high.

Calculating the difference in potency by measuring the

area under the

curve revealed an even greater difference, with

vitamin D3 more than

nine times more effective than D2.

 

Dr. Podell: This led the researchers to conclude:

“Clearly vitamin D3

is

the preferable form of vitamin D, and physicians using

vitamin D2

should

be aware of its markedly reduced potency and shorter

duration of

action”.

 

Don: Now, in my opinion, this information is valuable,

but I’m not sure

if it has as much practical significance as they seem

to think. They

gave one very large dose, and then measured what

happened over a 28 day

period.

How does that relate to those of us who take a 400 IU

dose of vitamin

D

every day as part of our supplement regimen?

 

Arnie: That’s a good point, Don, but everything else

being equal, if we

are going to take vitamin D, why not take the form

that seems to work

the best!

 

You folks might be interested in what form is used on

some of the

products we talk about on the show, or sell at Willner

Chemists.

 

Well, in Willvite, we use vitamin D3, or

cholecalciferol, the type

found

most effective in the study. The same is true for

Solgar, in their

VM2000, and Natural Factors in their Calcium,

Magnesium Citrate plus D

formula.

 

 

Interestingly enough, Centrum used ergocalciferol,

which is vitamin D2,

the type found less effective.

 

 

 

 

AIM Barleygreen

" Wisdom of the Past, Food of the Future "

 

http://www.geocities.com/mrsjoguest/Diets.html