Re: Vitamin A and Vitamin D3

Nutritional supplementation is a mind field with many differing schools of thought. Thats why its important do do plenty of your own research so you can make your own informed decisions.

Both A and D have been touted as the next best thing to sliced bread and also vilanized, Just like both Iodine and selenium have as well as a whole host of other nutrients.

Personally I think how much D you need depends on how much sun you get. I live in a colder climate so dont get a lot of sun in the winter and I am a fairly large guy so I take 5000IU.

I also feel there is a lot of evidence to support the need for additional nutrients when taking D. Namely A, K and magnesium and zinc.

I also feel weston price has some solid evidence to support an approximate 5:1 ratio of A to D so with that in mind I try and get at least 25,000iu of vit A.

vit K gets a little fuzzier since there is K1 and K2 and the body responds to them differently and then there is synthetic mk4 and mk7 versions of K2. The body seems to need both and have limitations on what it can get from food alone but that limitation seems to not apply to the synthetic version. So fo that reason I opt to use a product with all forms lef.org super K.

I also take 800-1200mg magnesium and plenty of zinc also.

Weston price recommends dosing of 9500 IU vitamin A and 1950 IU vitamin D when using one of their recommended brands of cod liver oil. Keep in mind synthetic versions and non fermented version of cod liver oil may not absorb as well and require much more.

here is some additional reading for you:

http://www.westonaprice.org/cod-liver-oil/cod-liver-oil-basics#clarify

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