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Donald Lee
12-22-2008, 11:15 PM
Important Cod Liver Oil Update (http://articles.mercola.com/sites/articles/archive/2008/12/23/important-cod-liver-oil-update.aspx):

What You Need to Know About Vitamins A and D in Cod Liver Oil

At least 2,000 genes, or nearly 10% of your genes, have been identified that are directly influenced by vitamin D, which in turn impact a wide variety of health issues, from preventing the common cold and flu to inhibiting at least 16 different types of cancer. There’s even evidence linking vitamin D to the process of brain detoxification of heavy metals such as mercury.

Widespread vitamin D deficiency has also been strongly linked to the childhood epidemics of autism, asthma, and diabetes, both type 1 and 2.

Vitamin A, which is essential for your immune system just like vitamin D, is also a precursor to active hormones that regulate the expression of your genes, and they work in tandem.

For example, there is evidence that without vitamin D, vitamin A can be ineffective or even toxic. But if you’re deficient in vitamin A, vitamin D cannot function properly either.

There are many problems with modern cod liver oil but one of the primary ones is that there is no standard definition of what constitutes cod liver oil. Manufacturers are free to add or subtract as much vitamin A or D as they see fit. In fact cod liver oil was discovered in the sewers of England several hundred years ago by starving children who drank it and scientists noticed they did not get rickets. Cod liver oil is in fact a highly processed food that was never consumed by humans prior to this.

Dr. John Cannell, head of the Vitamin D Council, along with 15 other researchers, recently released an article “Cod Liver Oil, Vitamin A Toxicity, Frequent Respiratory Infections, and the Vitamin D Deficiency Epidemic" in the November issue of Annals of Otology, Rhinology and Laryngology. In this paper Dr. Cannell raised questions about the efficacy of cod liver oil due to its highly variable and frequently excessive amount of vitamin A. Typically modern cod liver oil contains far less vitamin D than it used to, due to the deodorization process used today which removes much of this essential nutrient.

Dr. Cannell and other prominent researchers believe the vitamin A contained in most cod liver oil is excessive, and can reduce the effectiveness of vitamin D by inhibiting the binding of its active form to your DNA, effectively preventing its ability to regulate the expression of your vitamin D-responsive genes.

The Weston Price Foundation, of which I am an advisory member, holds a contradictory view. They believe vitamin D can only effectively target genes when its “partner receptor” is activated by vitamin A. If vitamin A is absent, certain molecules called co-repressors bind to the receptors and prevent vitamin D from functioning. It is their position that cod liver oil is still a highly recommended supplement.

After reviewing the evidence, I am personally convinced that there is sufficient vitamin A in the current American diet to facilitate sufficient vitamin D activation. This does not appear to be the case in third world countries, where cod liver oil, or some other preformed retinol supplement, would still be useful.

Garrett Smith
12-23-2008, 05:13 AM
The WAP is not going to take this well.

Allen Yeh
12-23-2008, 05:22 AM
Wap?

sarena kopciel
12-23-2008, 05:33 AM
Wap?
Weston A Price foundation (www.realmilk.org)

Will Moore
12-23-2008, 09:39 AM
I read this today also....this comes from one of those emails that Dr. Mercola blasts out. Don't accept it as the truth until all the facts are known; its just one study. Also, there are cod liver oil capsules on the market that have over a 2:1 ration of Vitamin D to Vitamin A. Personally, I use Carlsons cod liver oil capsules. One serving provides 100% of the RDA for Vitamin D and only 30% for Vitamin A. Therefore, what Mercola said cannot be applied to all cod liver oil. They are not all too heavy on Vitamin A and too weak on Vitamin D. Also, I tend to be skeptical about anything Mercola says, since his main goal seems to be selling you his Krill oil supplements.

Garrett Smith
12-23-2008, 10:23 AM
This is all very interesting information.

From what I've found on the subject this morning, there really is very little evidence of Vitamin A deficiency in "developed" countries, while there is a good history of Vitamin A toxicity, both acute and chronic.

A paper on Hypervitaminosis A: Its Broadening Spectrum (http://www.jeghers.com/pdfs/d1296.pdf) from the American Journal of Clinical Nutrition from back in *1958*....

A lot of interesting info on this post (http://www.vitamindcouncil.org/newsletter/2008-december.shtml) from the Vitamin D Council...

The crux of the problem is that a form of vitamin A, retinoic acid, weakly activates the vitamin D response element on the gene and perhaps blocks vitamin D's more robust activation. In fact, the authors of a 1993 study state "there is a profound inhibition of vitamin D-activated...gene expression by retinoic acid."

The key is having the proper ratio of vitamin D to vitamin A in your body. To obtain this proper D/A ratio, you must make a choice. (1) Either obtain the D/A ratio Nature intended—that is, the ratio the human genome evolved on—or (2) assume one knows better and intervene in a closed system, bypass the controls in the intestine, and inject active A directly into your blood by taking vitamin A or cod liver oil. Vitamin A production is tightly controlled in the body, the source (substrate) being carotenoids from vegetables in your intestine. The body uses these carotenoid substrates to make exactly the right amount of retinol for your body. That is, it is a closed, tightly regulated, system, one designed to perfection by Nature. When you take vitamin A as retinol, such as in cod liver oil, you intervene in this closed system and bypass the controls. Proceed at your peril.

Vitamin D is also a closed, controlled system and I don't recommend intervening in that system either. Vitamin D cholecalciferol is a substrate like carotenoids, it is not the active substance. Taking vitamin A as retinol is like taking activated vitamin D (calcitriol). Doing so bypasses controls and I have never recommended anyone take activated vitamin D except patients with renal failure under the care of a nephrologist. As long as your vitamin D (cholecalciferol) dose is not excessive, you are not intervening in a closed system, you are simply providing the vitamin D substrate. The body, if and when it has enough vitamin D substrate, will use what it needs and dispose of, or store, the rest.

Thus the goal is to provide all the vitamin A and vitamin D substrate the body would have obtained in a natural state, so the body can regulate both systems naturally. This is best done by eating colorful vegetables and by exposing your naked skin to equatorial sun every day. Since most of us can't do the later, and won't do the former, we have to take the same amount of vitamin D substrate we would have obtained living 100,000 years ago—and may want to take beta-carotene substrate in a multivitamin. As far as I know, low doses of beta-carotene (1,000–2,000 IU per day) will not do too much harm. The best way to get vitamin D substrate, as far as I can tell, is to take about 1,000 IU of vitamin D3 per every 25 pounds of body weight in the winter and stop all vitamin D in the summer and sunbathe. Alternatively, use a tanning bed when the sun is too low on the horizon to sunbathe. Remember, when you are outside, if your shadow is longer than you are, you are not making any vitamin D.
...
When patients present to their doctor with abnormal liver function tests or overt liver disease—and many hundreds of thousands do every year—how many physicians inquire about vitamin A or cod liver oil supplements? The authors below found 41 cases and warned that "chronic vitamin A consumption might represent an appreciable cause of chronic liver disease." But if you think these 41 cases are the only ones reported, think again. A PubMed search reveals nearly 100 reports on vitamin A-induced liver disease.
...
I admired everyone I met at the Weston A. Price Foundation when I spoke there several years ago, mainly because of their commitment to healthy soil. However, when I brought up toxicity of cod liver oil, the atmosphere quickly turned from science to religion. Not only did I warn them about cod liver oil, the vitamin A researcher they flew in, Dr. Noel Solomon, also warned them about cod liver oil. No use. With every word either of us spoke, the flasks flashed as members of the audience took swigs of their cod liver oil.
And from a past newsletter of Dr. Cannell's:
I am not convinced that because cod liver oil is "natural," it is therefore good. Tsunamis and strychnine are natural. In fact, cod liver oil is a processed food and Paleolithic man didn't drink it. There is evidence that at least one Paleolithic African women suffered severe vitamin A toxicity, probably from the liver she consumed. Chronic consumption of chicken liver caused vitamin A toxicity in twin girls.

A recent review of the literature found evidence that higher vitamin A levels are associated with bone problems. Women who consumed more than 15,000 units of vitamin A per day in food and supplements had a three and a half times higher risk for birth defects in their children than women who consumed less than 5,000 IU.

Vitamin A antagonizes the actions of vitamin D, probably at the receptor level, although that is not clear. The amount of vitamin A in one serving of liver antagonizes the rapid intestinal calcium response to physiological levels of vitamin D in man.

We just don't know if large amounts of vitamin A (more than 5,000 IU/day) causes problems when consumed with a large amount of vitamin D, as would be the case in people consuming large amounts of cod liver oil. A very well-written and entertaining rebuttal to my cod liver oil position, which I presented to the Weston A. Price Foundation, was recently published by that same foundation. However, Dr. Noel Solomon—a vitamin A researcher who spoke at the same conference—also cautioned against high vitamin A intakes.

In the end, my natural conservatism wins out. More is not better. What was the diet we evolved on? I know my Paleolithic ancestors didn't drink cod liver oil. Neither will I, unless my mother makes me, or until I have to choose between cod liver oil or nothing—and I don't.
I'm guessing if Dr. Mercola is choosing towards aligning with Dr. Cannell, then he won't likely be a board member of the WAP for much longer.

The point that the CLO today is not like the CLO of decades past is an extremely important one. This means that the CLO that Weston Price was using back then definitely is not the same as nowadays.

Interesting stuff from the Linus Pauling Institute on Vitamin A here (http://lpi.oregonstate.edu/infocenter/vitamins/vitaminA/).

I will be revising my Vitamin A recommendations based on this information, with the high end of retinol (preformed vitamin A, not carotenoids) being 5000iu per day for anyone.

Mike ODonnell
12-23-2008, 10:38 AM
even the top supplement is not perfect.....guess food always trumps supplments. More sardines anyone?

sarena kopciel
12-23-2008, 12:11 PM
even the top supplement is not perfect.....guess food always trumps supplments. More sardines anyone?

Thanks for the offer, had my sardines today for lunch. Along with some roasted organic broccoli, coconut milk ice cream and some homemade wheat free pumpkin and banana bread (almond meal based)!

Ben Fury
12-24-2008, 12:51 AM
The WAP is not going to take this well.

Confirmation bias is a bitch. Got to wake up every day, put on the thinking cap and DON'T TAKE IT OFF! Especially when someone gores your sacred cow... especially when someone says your workout's stupid... especially when someone says your super duper supplement or eating plan sucks!

Take a deep breath. Reach up to straighten your thinking cap (and be sure it's still on) and say something like, "Really? What EXACTLY doth sucketh about it?" and be prepared to listen closely to the answer... be prepared to admit that maybe, just MAYBE I'm NOT the smartest, most intuitive person on the planet. Maybe, this offensive person describing how I "sucketh" is telling me something I can use... maybe...

Maybe not. But I'll never know until I give them a fair listen!

WAP folks have come too far and ditched too much cultural conditioning to just trip and go down and fail to get up over something stupid like cod liver oil! Right? Guys? Gals? ... right? Hmmmmmmmm........ Do I hear the faint breathing of a Confirmation Bias in here? Or is it just the ventilation system? Hmmm...

George Mounce
12-24-2008, 04:49 AM
Not sure it is confirmation bias, but your last name is amazing Ben regardless.

Ben Fury
12-24-2008, 08:23 AM
Not sure it is confirmation bias, but your last name is amazing Ben regardless.

Thanks! That's the third spelling since the family came to America from Slovakia. First two spellings were hilariously badly pronounced by the locals. So my Grandpa finally just Americanized it to Fury and had done with it. People STILL sometimes screw up and pronounce it Furry. <sigh> Illitieracy is rampant. :(

Craig Loizides
12-24-2008, 02:29 PM
Here's the Weston Price take on Vitamin A:

http://www.westonaprice.org/basicnutrition/vitamina-osteo.html

Basically it says that vitamin A toxicity is primarily a vitamin D deficiency and that beta-carotene is neither adequate or fully safe.

I'm not sure who's right but from what I've read so far the WAP argument is more convincing.

Plus it's a lot easier for me to believe that vitamin A, D, E, and K and magnesium, calcium and phosphorous need to be in proper balance than it is for me to believe that 6 ounces of liver a week is toxic.

Garrett Smith
12-24-2008, 04:28 PM
I think the answer is somewhere in the middle on the A issue. Both sides are obviously cherrypicking studies that back their side.

There's only one liver per animal, so ODing on liver in past times (except with certain animals) seems less likely assuming the liver was equally divided among a group of people.

I have no idea how much CLO comes from one cod liver, but I bet it isn't much.

Ben Fury
12-24-2008, 04:36 PM
I hate playing "pick an expert."

Either the WAP people as represented by Chris Masterjohn's long review are right...
or...
John J. Cannell, MD; Reinhold Vieth, MS, PhD; Walter Willett, MD, DrPH; Michael Zasloff, MD, PhD; John N. Hathcock, MSc, PhD; John H. White, PhD; Sherry A. Tanumihardjo, MSc, PhD; D. Enette Larson-Meyer, PhD; Heike A. Bischoff-Ferrari, MD, MPH; Christel J. Lamberg-Allardt, PhD; Joan M. Lappe, PhD, RN; Anthony W. Norman, PhD; Armin Zittermann, PhD; Susan J. Whiting, MSc, PhD; William B. Grant, PhD; Bruce W. Hollis, PhD; and Edward Giovannucci, MD know what they're talking about and maybe cod liver oil has too much preformed Vitamin A retinols.

HELP!!!

We've got an amateur trying to take care of their health here. Let me check... yes, pulse and respiration are strong, but he looks bad...
IS THERE A CHEMIST IN THE HOUSE?!?!!!
:confused:

Bo Bolund
12-25-2008, 05:53 AM
I've tried a cod liver oil based vitamin d supplement. It made me really sick. At first I thought it was the vitamin d but when I switched to a synthetic vitamin d3 I felt much better. Natural may no always be the best. I've read in the papers lately that many fish oil brands contain rancid oil.

Craig Loizides
12-26-2008, 03:49 PM
I hate playing "pick an expert."

Either the WAP people as represented by Chris Masterjohn's long review are right...
or...
John J. Cannell, MD; Reinhold Vieth, MS, PhD; Walter Willett, MD, DrPH; Michael Zasloff, MD, PhD; John N. Hathcock, MSc, PhD; John H. White, PhD; Sherry A. Tanumihardjo, MSc, PhD; D. Enette Larson-Meyer, PhD; Heike A. Bischoff-Ferrari, MD, MPH; Christel J. Lamberg-Allardt, PhD; Joan M. Lappe, PhD, RN; Anthony W. Norman, PhD; Armin Zittermann, PhD; Susan J. Whiting, MSc, PhD; William B. Grant, PhD; Bruce W. Hollis, PhD; and Edward Giovannucci, MD know what they're talking about and maybe cod liver oil has too much preformed Vitamin A retinols.

HELP!!!

We've got an amateur trying to take care of their health here. Let me check... yes, pulse and respiration are strong, but he looks bad...
IS THERE A CHEMIST IN THE HOUSE?!?!!!
:confused:

A list of studies would be more useful than a list of PhDs. Some doctors have said that too much vitamin A is bad. WAP has studies showing that if vitamin D is high enough the level of vitamin A doesn't matter. So, are there any studies showing vitamin A causing problems with sufficient vitamin D? And at what level of vitamin A if vitamin D is at 5000-10000 IU per day? The answer is probably somewhere in the middle. I'll avoid polar bear liver to be safe.

Donald Lee
12-27-2008, 12:03 PM
A list of studies would be more useful than a list of PhDs. Some doctors have said that too much vitamin A is bad. WAP has studies showing that if vitamin D is high enough the level of vitamin A doesn't matter. So, are there any studies showing vitamin A causing problems with sufficient vitamin D? And at what level of vitamin A if vitamin D is at 5000-10000 IU per day? The answer is probably somewhere in the middle. I'll avoid polar bear liver to be safe.

I believe Dr. Mercola is in agreement that if Vitamin D levels are high enough, the Vitamin A can be counteracted, even at high levels. What he and others are arguing is that we get enough Vitamin A from food and do not get enough Vitamin D. So why compound a problem?

Craig Loizides
12-27-2008, 09:14 PM
Donald, thanks for clearing that up for me.

Dr. G ... are you still taking any dessicated liver? I was surprised to see that they don't list any vitamin A in the nutritional info. Is it destroyed in the processing? Or are they just not listing it?

Ben Fury
12-28-2008, 12:10 AM
Cod Liver Oil - Nutrition Info

Supplement Facts
Serving Size: 1 Teaspoon (5 mL)
Vitamin A 4615 International Unit 92%
Vitamin D 462 International Unit 116%
EPA (eicosapentaenoic acid) 554 Milligrams *
DHA (docosahexaenoic acid) 369 Milligrams *
*Daily value not established.

Vitamin A is fat soluble. Some folks swig this stuff like it's a cordial. How many swigs a day till it's toxic? If you're trying to get the 4-6000 IU of D per day that some experts are recommending, you'll get around 1000% of your Vitamin A if you're trying to get all that D from Cod Liver Oil.

WAP thinks this is safe? OK, it's a free country, but I'm not trying that experiment with my body.

Garrett Smith
12-28-2008, 06:06 AM
Donald,
I'm not currently taking any liver, I'm still having several people use it though.

As to why vitamin A isn't on the nutrition facts, I have no idea. I know that many types of dessicated liver, particularly the kind in tablet form, is defatted. That would likely take away the vitamin A. I have spoken to the Leviticus11.com folks over email about their product, they say it is all the original parts (minus the water, obviously).

Chris Forbis
12-28-2008, 05:29 PM
I recently started taking pretty large doses of Blue Ice High Vitamin CLO, in order to get a decent winter dose (3,000 IU) of Vitamin D. This meant 30,000 IU of Vitamin A. I started getting Vitamin A toxicity symptoms. Awful molting of my lips (chapped is too mild a term for what I was getting) and itchy patches of skin (around my pits). I went home for Christmas, not taking my CLO with me and the symptoms receded. The plan is to cut down on the CLO to 1,000/10,000 IU of A/D and supplement with some Vitamin D drops.

Ben Fury
12-28-2008, 06:38 PM
The plan is to cut down on the CLO to 1,000/10,000 IU of A/D and supplement with some Vitamin D drops.

You can get Now Foods, Vitamin D-3, 2000 IU, 120 Softgels for around $5 a bottle if you look around online.

Michael Miller
12-29-2008, 04:04 AM
Dr G, what dose of the Blue Ice Gold Therapuetics are you recommending to your patients now? Do any of your patients still use the Carlsons brand of CLO?

Garrett Smith
12-29-2008, 04:39 AM
Michael,
Some still use Carlson's.

I'm revising my standard Green Pastures recommendation to 1 capsule (or mL of liquid) per day plus 2400 mg EPA+DHA from fish oil plus enough supplemental vitamin D to get 2000iu per day total. The D could go up based on testing, but that's where it starts.

Yael Grauer
12-30-2008, 03:18 PM
WAP doesn't recommend the massive amounts of CLO that people take; I believe they recommend anywhere from 1 tsp to 1 tbsp/day.


Vitamin A is fat soluble. Some folks swig this stuff like it's a cordial. How many swigs a day till it's toxic? If you're trying to get the 4-6000 IU of D per day that some experts are recommending, you'll get around 1000% of your Vitamin A if you're trying to get all that D from Cod Liver Oil.

WAP thinks this is safe? OK, it's a free country, but I'm not trying that experiment with my body.

Garrett Smith
12-30-2008, 03:38 PM
http://www.westonaprice.org/basicnutrition/cod-liver-oil-menu.html
Children age 3 months to 12 years: A dose of cod liver oil that provides about 5000 IU vitamin A daily
Children over 12 years and adults: A maintenance dose of cod liver oil that provides about 10,000 IU vitamin A daily
Pregnant and nursing women: A dose of cod liver oil that provides about 20,000 IU vitamin A daily
1 mL or 1 capsule of Green Pastures Blue Ice Gold Therapeutics has 5000 A / 500 D. I don't remember the values in their "straight" CLO.

Chris, thanks for sharing. It's exactly your experience that needs to be heard. Even Green Pastures' products A/D ratio doesn't remove all risk of hypervitaminosis A. This is what I was concerned about when I read Mercola's and the Vitamin D Council's newsletters.

I had a roommate in college who got vitamin A toxicity from *carrots*. Sure, he ate a ton of them one night and he also had very strange liver metabolism (very tolerant of alcohol, immune to morphine). The doctors at the Student Health Center paraded him around for all to see, as they see it so rarely (if at all). So much for poor or non-existent (as some have claimed) conversion of carotenoids to Vitamin A!

sarena kopciel
12-30-2008, 05:27 PM
http://www.westonaprice.org/basicnutrition/cod-liver-oil-menu.html

1 mL or 1 capsule of Green Pastures Blue Ice Gold Therapeutics has 5000 A / 500 D. I don't remember the values in their "straight" CLO.


Ok so I have the straight CLO from Blue Ice. The bottle reads (per 2 capsules) 5000IU/Vit A
500IU Vit D.
EPA 150 mg
DHA 100mg

What does should I be using?

Yael Grauer
12-30-2008, 10:16 PM
Sarena take two caps and then some additional fish oil too.

Garrett Smith
12-31-2008, 04:40 AM
Sarena,
I'd go with what Yael said. I add 2400mg of EPA+DHA daily plus 2000iu more of D3.

sarena kopciel
12-31-2008, 06:16 AM
OK thanx guys, thats what I have been doing, espec now in winter. I have been dosing as 2 CLO (Blue Ice Brand) and 2 fish oils that I have from you Dr. G!

Michael Miller
01-01-2009, 09:53 AM
Dr G, i apologise if im mistakin but i thought you had mentioned in the past about staying away from D3 supps? Whats a good D3 to be using?

Do you feel that the Carlsons CLO is still a good product or is it to low in vit A?

What about high vitamin butter...does it need to be present like the WAP people are suggesting in order to derive real benefit from CLO?

Garrett Smith
01-01-2009, 12:31 PM
Michael,
The D3 confusion came about as I have been figuring out the "vitamin D-like" mechanism of the nightshades I first heard of from Dr. Childers of www.noarthritis.com . I've heard too many positive clinical results from supplemental D3 (and avoiding nightshades) to continue recommending avoiding it.

I think Carlson's is fine. The lower Vitamin A is a good thing, IMO.

Taking A & D with fat is a good idea. The "X-factor" in the butter oil is now theorized to be Vitamin K, which would further synergize with the other fat-soluble vitamins.

I use the Green Pastures Blue Ice Gold Therapeutics (CLO + a little butter oil) because the combination is already taken care of.