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Cod Liver Oil for Crohn's Disease - A Warning


Naples, Florida
As you may or may not know, Vitamin D has been shown to be highly beneficial for many people with Crohn's Disease. Many here take multivitamins and I've seen some people discuss taking cod liver oil. I came across a very fascinating article today discussing the necessary ratios of vitamin A to vitamin D. A few excerpts:

"Although activated vitamin D and vitamin A signal through common cofactors, they compete for each others function. Retinoic acid antagonizes the action of vitamin D and its active metabolite. In humans, even the vitamin A in a single serving of liver impairs vitamin D's rapid intestinal calcium response. In a dietary intake study, Oh, et al, found that a high retinol intake completely thwarted vitamin D's otherwise protective effect on distal colorectal adenoma, and they found a clear relationship between vitamin D and vitamin A intakes, as the women in the highest quintile of vitamin D intake also ingested around 10,000 IU/d of retinol."
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 at least 5,000 IU of vitamin D3 per day 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 tall, you are not making much vitamin D.
The quote below is very interesting to me considering Crohn's Disease is a first world disease. One that benefits from vitamin D intake...
"Another recent Cochrane meta-analysis concluded that although vitamin A significantly reduced the incidence of acute lower respiratory tract infections in children with low intake of retinol, as occurs in the Third World, it appears to increase the risk and/or worsen the clinical course in children in developed countries."
"As the prevalence of vitamin A deficiency in the United States is apparently much lower than the prevalence of subclinical vitamin A toxicity, we cannot recommend cod liver oil for either adults or children. (We exclude fish body oil from our warning, as it contains no vitamin A or vitamin D but is a very important source of omega-3 fatty acids.) For example, in a recent assessment of serum retinyl esters in a group of obese individuals, four percent had levels >10% of total retinol which usually indicates hypervitaminosis A. Instead, a diet rich in carrots, sweet potatoes, cantaloupe, and other orange fruits and vegetables will supply all the carotenoids the body needs to make retinol without the potential for hypervitaminosis A, especially when additional preformed retinol already exists in dairy products, eggs, and fortified cereal. We wish our diet were as rich in vitamin D. "

Long story short, don't take cod liver oil or vitamin A as a retinol.
One more VERY interesting fact for you. You know all those lawsuits out there regarding Accutane possibly causing Crohn's Disease or Ulcerative Colitis? Guess what the active ingredient of Accutane is? It's essentially Vitamin A.

I hope this information is helpful :)


lol Accutane was the first thing I thought of while reading about Vitamin A, as like you said, it is, basically, extremely high concentration of Vit A.

Other interesting thing to note "research" is showing too much Vit D can cause the heart to beat too fast (sorry, posting from phone, so will add links when I get to puter).

I think best advise: eat as healthy as you can, and when concerned, get your blood tested for vitamin deficiencies! Great info though! :)
Well crap, I just bought two bottles of Cod Liver Oil.

David- Just curious, since you seem to be the authority on supplements, I have a bottle of Calcium, Magnesium, Zinc and D3. The supplement facts say the Daily Value for each are as follows: Vitamin D3 200 IU- 50%, Calcium 333 mg- 33%, Magnesium 133 mg- 33%, and Zinc 5 mg- 33%

Does this mean I should take it three times a day? I also take a separate Vitamin D because 200 IU is nowhere near enough! Also, do you have any recommendations for brand/type of Fish Oil?

Thanks a million!


Naples, Florida
If I wrote what I wrote today, I would add, "Get tested for vitamin A". If you happen to be deficient, then maybe cod liver oil is a good idea. If not, I think there are better options for vitamin D and fish oils.

Avw, I'm definitely not an authority. People here like Beach know way more than me, I'm just trying to help where I can. In regards to your supplement, I'd take that once a day along with your higher dose D3 as that's got great D cofactors in it. I wouldn't take more than one a day unless you are deficient in all of those (there's a decent chance, get tested to find out).

It's all about getting tested. Testing lets us track our progress over time, helps us determine dosage, let's us know what we should supplement, etc. Supplementing what we don't need can cause problems.

As for fish oil, I personally take neptune krill oil.
Thanks David! I know you're not literally "the authority" but you are very knowledgeable and I value your opinion!

I was tested about a month ago and was deficient in all of those but not seriously lacking vitamin A, and I'm in my worst flare yet (about to be put on TPN), so I'm sure my levels have dropped even further. My main reason for wanting to beef up my Magnesium, Potassium, and Zinc levels is because I've read in a few places that these will help heal/prevent fistulas and abscesses. Not sure if this is true, but after 4+ surgeries in the last eight weeks on abscesses... I'll try anything!


Naples, Florida
Hi Avw,

When they found you to be deficient in all of those, did they provide you with any dosage recommendations?

This is a wonderful article on magnesium. For someone who is deficient, they recommend a minimum of 600mg per day. For a Crohnie who is deficient, I suspect that needs to be even higher.

The problem with Zinc is zinc toxicity is a very real thing and can happen at dosages as low as 50mg/day. As a Crohnie, I'm guessing you could do 50mg pretty safely but I'd split dose it and keep very close track of your symptoms to see if they worsen as Zinc toxicity can mimic symptoms of IBD.

I'm not yet well educated enough on potassium or calcium to the point I feel comfortable commenting on dosages for people with Crohn's Disease, sorry :( Recommended intake is easy to regurgitate, but the problem is, if you have chronic diarrhea or constipation, are on meds like prednisone, and/or have problems absorbing it, recommended intake will be way off. This is why I think getting regularly tested is SO IMPORTANT. It will help you figure out a dose that is right for you.

FYI, Prednisone, which I see you're on, also leads to loss of vitamin C.

If you're deficient in all over those, did they also test your D, B12, folate, and K levels? I know they didn't test other B vitamins (though they should) but I suspect deficiency is more common in Crohnies than most realize. You may want to consider discussing taking a B complex with your doctor. But definitely get B12 and folate levels tested if they haven't.

You also need to balance all this out with your TPN. For example, if your TPN intake of zinc is 40mg per day then you sure as heck don't want to take 50mg on top of that. Be very careful!
I know they didn't test for D, wish that were included in the panel, not sure why I have to specifically request certain things. My doctor never recommends dosages, I'm not sure if he even looks at my labs. He's a real gem. The K levels are 4.4, which they marked as normal. I don't think they tested for B12 or folate either, but I have been on a Super B Complex that includes Ascorbic Acid for about year. Makes a huge difference. I'm also already noticing a big difference since supplementing Vitamin D, more energy, less brain fog, and less depression. Always great things!

Are there specific names for tests that I should request? I don't know if I am not asking for the right things or if my doctor is as incompetent as he is indifferent. At least I wont have to deal with him much longer, Chicago bound early September to start pre-testing with Dr. Burt! :)

Also, would you happen to know anything about thyroid levels? I requested the TSH and the results were 0.447 which were flagged as normal, but I know what is considered normal is debatable... Thanks again!


Naples, Florida
I would DEFINITELY get your folate and B12 levels tested. D would be a good idea as well so you can start tracking your progress.

If you can't get in for an appointment, there's always this. That's what I use since I have a $7,000 insurance deductible so that's cheaper for me.

I don't know much about thyroid levels other than vitamin D being crucial to thyroid function. Sorry.