Re: Mega C and exercise don't mix

[Guest guest]

,

> Here's an interesting blog post that describes a journal article about

> negative effects of vitamin C supplementation with exercise:

>

http://fanaticcook.blogspot.com/2009/02/vitamin-c-supplementation-and-exercise.h\

tml

Thanks very much for posting this! Definitely a surprising finding,

but the mechanism proposed makes sense. I have wondered whether taking

high-dose vitamin C might decrease endogenous antioxidant production

and this appears to confirm that. I'm going to read the study when I

have more time and see if I agree with their methods and conclusions.

Do you know what previous studies have suggested? There must be older

studies on antioxidant levels and endurance out there.

I am currently taking 2-3g of ascorbate a day but I may stop that now,

especially because I'm an (amateur) endurance athlete!

Tom

[Guest guest]

What type of vitamin C? Ascorbic acid which isn't the complete form of vitamin

C? My two favorite are the plant grown C-500 from www.lifestar.com and whole

food source seabuckthornberry from www.sibu.com

Thank you,

Holt

Sent from my iPhone

On Feb 15, 2009, at 8:06 AM, " " <oz4caster@...> wrote:

Here's an interesting blog post that describes a journal article about

negative effects of vitamin C supplementation with exercise:

http://fanaticcook.blogspot.com/2009/02/vitamin-c-supplementation-and-exercise.h\

tml

Here's a summary excerpt:

Findings (for 1 gram of supplemented vitamin C per day)

1. Vitamin C reduced endurance

2. Vitamin C reduced the number of mitochondria (energy-producing

factories) bodies make in response to exercise/stress.

3. Vitamin C also reduced the amount of endogenous (made by our body)

antioxidants.

Here's the original journal article, which I haven't read yet:

http://www.ajcn.org/cgi/content/full/87/1/142

[Guest guest]

--- Tom Jeanne <tjeanne@...> wrote:

> I have wondered whether taking

> high-dose vitamin C might decrease endogenous antioxidant production

> and this appears to confirm that. I'm going to read the study when I

> have more time and see if I agree with their methods and conclusions.

> Do you know what previous studies have suggested? There must be older

> studies on antioxidant levels and endurance out there.

Tom, I haven't read much else about it. I'll be very curious to hear

what you think of the journal article, especially since you have read

a lot more about vitamin C than I have

[Guest guest]

--- Holt <danthemanholt@...> wrote:

> What type of vitamin C? Ascorbic acid which isn't the complete form

of vitamin C?

, I haven't read the journal article yet, but I'd be willing to

bet they are using refined ascorbic acid, since that's the form of the

vast majority of C supplements. Tom Jeanne has pointed out before

that many studies show that the health-related attributes associated

with vitamin C are entirely related to ascorbic acid and not to

associated flavanoids and other compounds found in food sources of

vitamin C.

[Guest guest]

This kinds weakens the argument? How much naturally occuring vitamin c is safe

to consume?

Sent from my iPhone

On Feb 15, 2009, at 2:16 PM, " " <oz4caster@...> wrote:

--- Holt <danthemanholt@...> wrote:

> What type of vitamin C? Ascorbic acid which isn't the complete form

of vitamin C?

, I haven't read the journal article yet, but I'd be willing to

bet they are using refined ascorbic acid, since that's the form of the

vast majority of C supplements. Tom Jeanne has pointed out before

that many studies show that the health-related attributes associated

with vitamin C are entirely related to ascorbic acid and not to

associated flavanoids and other compounds found in food sources of

vitamin C.

[Guest guest]

--- Holt <danthemanholt@...> wrote:

> This kinds weakens the argument? How much naturally occuring

> vitamin c is safe to consume?

, I checked the journal article and it simply said the humans

tested received daily doses of 1 g of vitamin C. However, if the

vitamin C was from a food source I think they would have said so, thus

I am fairly confident they were using refined ascorbic acid. Since

natural vitamin C in food has other co-factors, I would not

necessarily expect the same results if the study were repeated using

the same vitamin C dose, but from a food source high in vitamin C,

such as acerola.

As far as how much is safe, I've read about people taking vitamin C to

bowel tolerance and even higher, which is many grams per day. I think

the real question should be how much vitamin C is optimal? My guess

is that most of us getting a good traditional food diet don't need a

lot of vitamin C, not much more than you get with a little fruit and

vegetables each day. Since vitamin C is similar in structure to

glucose, people eating a lot of refined carbs might need more vitamin

C than those on a low-carb diet.

It looks like a 2 g/day dose is enough to interfere with glucose

metabolism:

Megadose of vitamin C delays insulin response to a glucose challenge

in normoglycemic adults

http://www.ajcn.org/cgi/content/abstract/60/5/735

=====================================================

Plasma glucose was significantly elevated 1-h postprandial in vitamin

C-saturated subjects vs those taking a placebo. The plasma insulin

response curve was shifted rightward in vitamin C-saturated subjects

relative to baseline: plasma insulin was significantly depressed at

0.5 h postprandial but significantly elevated at 2 h postprandial.

These data indicate that elevated plasma AA delays the insulin

response to a glucose challenge in normoglycemic adults, thereby

prolonging the postprandial hyperglycemia. These effects might be

partially explained by the competitive inhibition of glucose transfer

into pancreatic beta cells by high concentrations of circulating AA.

=====================================================

Where AA is ascorbic acid.

[Guest guest]

I do wonder if there's a time effect, tho, like if you're c-deficient

and suddenly start taking it or if you've been taking it for years

and your body is acclimated to it. My brother-in-law, an MD, is a

marathon runner. He's done three marathons in three days before over

a long weekend. He takes 2 grams of C a day. The vitamin C does

help the body create elastase, which could prevent sports injuries

like torn muscles, etc.

The study said it chose sedentary men - why were they sedentary? Did

they have some other health ills that made exercising uncomfortable

for them? What with the pharmafia going after B6 and Vitamin D, I

find any such journal article a little fishy. There's a host of bad

science out there sponsored by special interests to help them prove

or disprove things.

When I was using very high doses of vitamin C for lyme disease,

someone told me about using a rebounder (mini trampoline) for moving

the lymph. I started out getting tired at around 15 jumps (I was

sick!) and after a short time could jump over 100 jumps without being

significantly tired. Others on the salt/c group who are still on

high doses of vitamin C, like 3-6 grams a day, report great stamina,

which is a significant improvement over how they felt before. They

have taken up cross-country skiing, cycling, etc. as their health

improved. I believe this would have been impossible if vitamin C

really caused the poor gains the study indicated.

Actually, I felt like the vitamin C increased my endurance and

stamina because it got rid of the oxalic acid so I never got sore

muscles or even much muscle fatigue after over-doing it.

--- In , " Tom Jeanne " <tjeanne@...>

wrote:

>

> ,

>

> > Here's an interesting blog post that describes a journal article

about

> > negative effects of vitamin C supplementation with exercise:

> >

> http://fanaticcook.blogspot.com/2009/02/vitamin-c-supplementation-

and-exercise.html

>

> Thanks very much for posting this! Definitely a surprising finding,

> but the mechanism proposed makes sense. I have wondered whether

taking

> high-dose vitamin C might decrease endogenous antioxidant production

> and this appears to confirm that. I'm going to read the study when I

> have more time and see if I agree with their methods and

conclusions.

> Do you know what previous studies have suggested? There must be

older

> studies on antioxidant levels and endurance out there.

>

> I am currently taking 2-3g of ascorbate a day but I may stop that

now,

> especially because I'm an (amateur) endurance athlete!

>

> Tom

>

[Guest guest]

Megadosing C to treat lyme and getting a lot better stamina seems like

it would be a whole different story since the lyme would be causing

many other problems in the body. I'm not sure you can compare these

two things that easily...but it would be nice to see a study using

well seasoned athletes comparing their performance with and without

high doses of vit C.

I personally think of the many stories of natives running for hours at

a time without problems. They had extreme endurance and certainly

didn't use Ascorbic acid.

-

--- In , " haecklers " <haecklers@...>

wrote:

>

> I do wonder if there's a time effect, tho, like if you're c-deficient

> and suddenly start taking it or if you've been taking it for years

> and your body is acclimated to it. My brother-in-law, an MD, is a

> marathon runner. He's done three marathons in three days before over

> a long weekend. He takes 2 grams of C a day. The vitamin C does

> help the body create elastase, which could prevent sports injuries

> like torn muscles, etc.

>

> The study said it chose sedentary men - why were they sedentary? Did

> they have some other health ills that made exercising uncomfortable

> for them? What with the pharmafia going after B6 and Vitamin D, I

> find any such journal article a little fishy. There's a host of bad

> science out there sponsored by special interests to help them prove

> or disprove things.

>

> When I was using very high doses of vitamin C for lyme disease,

> someone told me about using a rebounder (mini trampoline) for moving

> the lymph. I started out getting tired at around 15 jumps (I was

> sick!) and after a short time could jump over 100 jumps without being

> significantly tired. Others on the salt/c group who are still on

> high doses of vitamin C, like 3-6 grams a day, report great stamina,

> which is a significant improvement over how they felt before. They

> have taken up cross-country skiing, cycling, etc. as their health

> improved. I believe this would have been impossible if vitamin C

> really caused the poor gains the study indicated.

>

> Actually, I felt like the vitamin C increased my endurance and

> stamina because it got rid of the oxalic acid so I never got sore

> muscles or even much muscle fatigue after over-doing it.

[Guest guest]

>

> Thanks very much for posting this! Definitely a surprising finding,

> but the mechanism proposed makes sense. I have wondered whether taking

> high-dose vitamin C might decrease endogenous antioxidant production

> and this appears to confirm that. I'm going to read the study when I

> have more time and see if I agree with their methods and conclusions.

> Do you know what previous studies have suggested? There must be older

> studies on antioxidant levels and endurance out there.

>

> I am currently taking 2-3g of ascorbate a day but I may stop that now,

> especially because I'm an (amateur) endurance athlete!

>

> Tom

>

Ah. This information now helps with something else. I've just been

reading that massive doses of ascorbic acid can help disrupt the

progesterone cycle in women and, when taken in the very early stages

of pregnancy, can prevent implantation and induce a

miscarriage/spontaneous abortion (6 grams or more of ascorbic acid,

without bioflavinoids, per day for 6+ days - per Susun Weed).

Inferring from studies in the literature, it does this by reducing the

antioxidant levels in the uterus (can't find the pubmed ref offhand

anymore). Initially, I was wondering how taking lots of an

antioxidant (vitamin C) could reduce antioxidant levels but if

endogenous antioxidant levels fall (with increased ascorbate w/o

bioflavinoids) perhaps that is how the uterine condition changes.

-j

[Guest guest]

,

> My guess

> is that most of us getting a good traditional food diet don't need a

> lot of vitamin C, not much more than you get with a little fruit and

> vegetables each day.

Hmmm....all meat dieters don't seem to need any vegetable sources.

--

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many people do. If you have a strong informed opinion, don't keep it

to yourself. Try and help people and make the world a better place. If

you strive to do anything remotely interesting, just expect a small

percentage of the population to always find a way to take it

personally. F*ck 'em. There are no statues erected to critics.

- Ferriss