What's the difference between Vitamin D and D3?

I am confused about the difference between Vit. D and
Vit. D3. Can someone help me? Also, I spoke with a doctor with expertise in HRT therapy yesterday. He is from Australia and said we should be taking 4000 of Vit.D
(or D3?) regularly.

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From what I understand there are Vit D2 known as ergocalciferol and vit d3 known as choledalciferol
D3 is the better one more natural one as D2 is synthetic and binds poorly with protein. I am vit d deficient and building up on D3 but it takes a long while and on 3000 I U's a day.

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Go to www.vitamindcouncil.org for tons of helpful info on vit D. The best way to determine how much vit D you need is to have a 25-OH vit D test done to see how much you have now. Then you'll know if you're OK with what you're doing or if you should add more. If you have to add, definitely D3 is the right one to use. It's the natural form produced by sunlight on skin. Be aware that there are a few diseases, like lymphoma, sarcoidosis and leukemia, which affect serum calcium. The effects of supplemental Vit D may require monitoring in people with these diseases.

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Hi Jacquelin, Alli and Duranee1: Duranee1 is correct, the Vitamin D Counsel is an excellent resource for this info, I read a lot at that site. Duranee, I used to read all the books Linus Pauling put out, is he still considered a leader in this field? Also, is he still alive? My mom was a big supplement fan, and started my use at a very young age, and her heroes were Linus Pauling, Adell Davis and that funny looking couple (can't remember their names) but they were popular in the 70's, and really into beta carotene. Well maybe they weren't funny looking but at the time, and being a teenager, I thought so ;) Does anyone know who I'm referring to?

Jacqueline, when I was taking D, I only took D3, plus I get some sun living in the desert. My only problem is every time I take any Ca or D my Ca goes up (okay if I wasn't hypercalcemic) and my D 25 goes down, maybe I'm from Mars and I don't know it :o)

Have you ever heard of vit D supplements lowering your 25 hydroxyvitamin D, and raising your Ionized Ca?

Anyway, good luck with the D3!!!

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I'm sorry, but I don't know much about that. I have an idea, though. Go into the net and put in Dr. Shames. You will be directed to thyroidpower.com. He is located in California and, in addition to his regularpractice, will work with people over the phone--He calls these coaching sessions.
Coaching sessions are not, however, covered by insurance. A few weeks ago I had a coaching session. Before the session, I took blood and saliva tests
which he evaluated. I think he's brilliant, and he gave me good advice about increasing the dose of my thyroid medication and explained what was probably going on re my parathyroid. He has written books and may be the person that can help you.

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