Thyroid UK
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What are good B12, Vit D and Folate levels?

I am waiting for my results and I am trying to conceive. Could you please tell me what good levels/numbers for B12, VIT D and Folate are, so I can plan if I need to get hold of these vitamins too.

Not sure if thyroid affects these levels?

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B-12: Measures an essential vitamin, B12, which can be low in hypothyroid patients due to low stomach acid. We noticed repeatedly that an optimal B12 lab result is in the upper part of the range, such as the upper quarter at least. It is NOT optimal to simply be “in range”. For example, if your range is similar to 180-900, a healthy level appears to be 800 or higher. In the 500-800 range, you can benefit from taking B12 lozenges, specifically Methylcobalamin. It has been shown in studies that patients with labs under 350 are likely to have symptoms, which means the deficiency is very serious and has gone on for a few years undetected. Lab ranges are much too low for B12…in Japan the bottom of the range is 500. The urine test Urinary Methylmalonic Acid, also called the UMMA, can be added since it is a very sensitive detection and if high, will reveal a true B12 deficiency.

FOLATE: Also sometimes called “folic acid”, this is a b-vitamin which can be low in hypothyroid patients. Folate is important for prenatal development, as well as your blood cell health. Folate works with B12 in the use and creation of proteins. It’s “folate” thats needed instead of “folic acid”, especially if you have MTHFR. Standard range is 3-17, so optimal would be at least the top third of that. Higher for MTHFR.


From Stop the Thyroid Madness website.

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For vitamin D ideal is around 100 nmol/L for many people, but not all. Some people don't do well on vitamin D.

Be aware that in the US different units are used (ng/mL) and they are not equivalent to nmol/L. 50 nmol/L is not the same as 50 ng/mL. Take account of this when reading info on the internet.

The supplement must be vitamin D3 (cholecalciferol), NOT D2 (ergocalciferol). Don't buy anything which doesn't say which one it is.

It should be taken with some fat or your fattiest meal of the day.

Taking vitamin D has a side effect of raising calcium levels. If you already take a calcium supplement it wouldn't be a good idea to continue taking it once you start supplementing vitamin D. Having high calcium levels are definitely not a good idea.

When you raise calcium levels because of vitamin D supplementation it is desirable to make sure that calcium ends up in the bones and not lining the arteries. In order to achieve this it is necessary to supplement vitamin K2 (NOT K1 or K) along with vitamin D3.

It is possible to overdo vitamin D supplementation so do get tested.

Vitamin D should be taken at least four hours away from thyroid meds.

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Can you recommend a good vitamin K2 and should this be taken at the same time as the Vitamin D?

I take the BetterYou Dlux 3000 spray and would like to take the K2 as I'd like to make sure I try and prevent any problems.

The more I read the more supplements I end up taking... I'll soon be rattling when I walk ;)




These articles on the subject of Vitamin K are worth reading :

I can parrot the information about vitamin K2 quite easily. But because I don't really understand the science behind it I wouldn't want to recommend any particular supplement.

I just decide on the basis of the unscientific method - I read reviews and check prices and I'm not loyal to any particular brand.


For vitamin D to convert ng/ml to nmol/l times the value by 2.5 To convert nmol/l to ng/ml divide the value by 2.5

In addition to k2 you may also want to supplement with magnesium . The alternative is to make sure you eat a handful of nuts like almonds, cashews or Brazil nuts a day. Nuts have the advantage of having other vitamins and minerals in them.

As vitamin D is fat soluble you can calculate your weekly dose then take it once weekly or divide it into 3 and take it every other day. This just limits the number of pills you need to take everyday.

You cannot do this with other supplements as for example the B vitamins are water soluble and taking large doses will just mean they are excreted out in your urine.

You can take too much vitamin D but this is rare. So while the literature worries about people taking over 4,000IU a day if you are deficient and most importantly have had a blood test you can take more. The amount you should take depends on your blood test result.

There are arguments over whether vitamin D raises calcium levels. Some people are put on a vitamin D and calcium supplement by their doctor. Most who have adequate calcium levels are not. Again this should be tested and if it is not tested then don't supplement calcium as most Western diets are sufficient in calcium even if you cannot drink milk, as you can get calcium from other food sources like green leafy vegetables and oily fish.

Further sources of information are the Vitamin D council website.


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