Vitamin dosage guidance: I’ve bombed recently... - Thyroid UK

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Vitamin dosage guidance

TiredMummy profile image
16 Replies

I’ve bombed recently & reassessing EVERYTHING from thyroid meds to HRT and now vitamins. I think I’ve been getting things wrong…..Does anyone know the optimal dosage we should take daily for the following:

Vitamin C - I currently take 3 x 750mg (2,250mg in total)

Zinc - I currently take 30mg daily

Magnesium- I currently take magnesium citrate 170mg daily

Iron - I currently take 20mg daily

I’ve also been taking a multivitamin but I’m going to stop that so I’ll also need to start taking these vitamins individually if people think the help support the thyroid? I’ve no idea what levels to go for and there are conflicting views on websites:

Vitamin D

K2 - hoping I can go with one combined with Vit D

Vit E - not sure I need this but menopausal so may help

B vitamins (my multivitamin included all of the Bs….)

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TiredMummy
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16 Replies
SeasideSusie profile image
SeasideSusieRemembering

TiredMummy

Does anyone know the optimal dosage we should take daily for the following:

It really depends on what your levels of key nutrients are, if you need the dose your on or more or less or even need to supplement.

Vitamin C - I currently take 3 x 750mg (2,250mg in total)

Vit C is a water soluble vitamin so any excess is excreted. As long as you don't develop diarrhoea than you can probably continue with this, it boosts immune system so can be helpful.

Zinc - I currently take 30mg daily

Did you test to see if you need to take zinc? Zinc and copper should be balanced and we hypos often have one high and one low, so we really need to know if we need to take it.

Magnesium- I currently take magnesium citrate 170mg daily

Testing magnesium is unreliable. About 99% of magnesium is stored in bone, muscles and soft tissues, leaving about 1% in the blood. So testing what's in the blood isn't giving an accurate picture of our magnesium status. That said, many of us hypos are low in magnesium.

The usual recommended dose on the pack is around 350-450mg daily.

With magnesium citrate, this form is helpful if constipated. You will know if you are taking too much because your stools will become loose or you'll develop diarrhoea so you'd cut back if that happened.

Iron - I currently take 20mg daily

Have you had an iron panel done and know that you have iron deficiency? If not maybe you shouldn't be supplementing iron.

I’ve also been taking a multivitamin but I’m going to stop that so I’ll also need to start taking these vitamins individually if people think the help support the thyroid? I’ve no idea what levels to go for and there are conflicting views on websites:

Test to get levels of key nutrients and these are what is generally recommended here:

Vitamin D -

The Vit D Society and Grassroots Health recommend a level of 100-150nmol/L, with a recent blog post on Grassroots Health mentioning a study which recommends over 125nmol/L. So post your result for suggestions as to what dose you may need.

K2 - hoping I can go with one combined with Vit D

If you need D3 then the amount of K2-MK7 needed is said to be 90-100mcg for up to 10,000iu D3.

Vit E - not sure I need this but menopausal so may help

I've never taken it so can't help. Be aware it's a fat soluble vitamin and any excess can't be excreted so it gets stored and may lead to toxicity. The fat soluble vitamins are A, D, E, K.

B vitamins (my multivitamin included all of the Bs….)

Testing B12 and Folate will tell you if you need to supplement these. Often, if you do, a good quality, bioavailable B Complex is all that is needed, a separate B12 (in addition) may be needed for a short while if B12 level is low but not low enough to be B12 deficiency.

B12 is recommended to be at least 550pg/ml but better is around 900-1,000pg/ml (particularly in older people).

Folate is recommended to be at least half way through it's range.

But really, don't supplement anything unless you have tested first and know that you need to.

TiredMummy profile image
TiredMummy in reply toSeasideSusie

I’ve just been scouting around & Medichecks Advanced Thyroid Function test would cover Vit D, B12, folate & iron. I will need to test my thyroid levels in 6 weeks-ish anyway so would this test cover everything I need for that too? It includes FT4, FT3. I’ve changed both my Levo & T3 dosing so would this be the preferred thyroid test for me anyway? I’ll have to find another test for copper, magnesium, zinc and selenium (trying to avoid forking out for a nutritionist again as they love you coming back again & again & it gets ridiculously expensive!).

humanbean profile image
humanbean in reply toTiredMummy

I’ve just been scouting around & Medichecks Advanced Thyroid Function test would cover Vit D, B12, folate & iron.

The Medichecks test you've mentioned tests Ferritin (iron stores) rather than Iron. They aren't the same thing.

People who have low levels of ferritin could have low iron, high iron or any level in between.

Ditto with high levels of ferritin.

Ditto with any level of ferritin in between.

More info about iron and the potential problems it can cause is available in this link :

healthunlocked.com/thyroidu...

A good iron panel test is this one :

medichecks.com/products/iro...

You can get a discount code for 10% off here :

thyroiduk.org/help-and-supp...

Testing iron and ferritin should always be done under the same circumstances as testing thyroid hormones i.e. fast for 12 hours before the blood draw, apart from water which can be drunk freely. Blood should be taken before 9am and before breakfast.

It is a good idea to stop taking any iron supplements for 5 - 7 days before taking blood. And don't eat meals with a heavy iron content for 24 hours before taking the blood sample for the test.

SeasideSusie profile image
SeasideSusieRemembering in reply toTiredMummy

The Advanced Thyroid test will test the full thyroid panel and the nutrients. If your ferritin is low you'd probably benefit from the iron panel that Humanbean has mentioned, but you might just want to do the Advanced Thyroid first. Don't take any iron tablets in the week before any iron/ferritin test.

I’ll have to find another test for copper, magnesium, zinc and selenium

Magnesium is included in the Blue Horizon equivalent to the Medichecks tet (BH Premium Gold). However, as mentioned above testing magnesium is unreliable. About 99% of magnesium is stored in bone, muscles and soft tissues, leaving about 1% in the blood. So testing what's in the blood isn't giving an accurate picture of our magnesium status.

A red cell magnesium test is the better indicator of magnesium status, not the standard serum magnesium test. Red cell magnesium test is expensive and not readily available. It requires phlebotomy and absolutely must reach the lab within 24 hours so probably requires a hospital blood draw. Personally I wouldn't bother with it.

Cerascreen do a mineral test which includes zinc and magnesium but not copper. It also includes serum magnesium but, as I mentioned, it's of no real use.

Personally I would just concentrate on the key nutrients included in Medichecks test for now.

Fruitandnutcase profile image
Fruitandnutcase in reply toSeasideSusie

There’s a really good article about magnesium in the TUK magazine Harmony this week. Explains a lot about it.

humanbean profile image
humanbean in reply toSeasideSusie

This test from BH might be of interest to some people :

bluehorizonbloodtests.co.uk...

The test is more expensive than most of the tests people do, but it does tell you about some things that aren't very often included in test bundles, or which are expensive on their own.

SeasideSusie profile image
SeasideSusieRemembering in reply tohumanbean

Well spotted HB. That could be useful for some members. And fingerprick too - bonus!

humanbean profile image
humanbean in reply toSeasideSusie

I did wonder how well the BH Folate test (included in that bundle) will actually work with a finger-prick test, given how often they fail.

SeasideSusie profile image
SeasideSusieRemembering in reply tohumanbean

I do their Premium Gold test once a year and that includes folate. I always do it as a fingerprick test and never had one fail to produce a folate result. I think it's all down to making sure there's enough blood in the tube, not taking too long to collect the sample, and just gently inverting the tube rather than shaking it.

humanbean profile image
humanbean in reply toSeasideSusie

They test biotin? But I thought that interfered with almost every test they did? Is the test done after a week of avoiding B Complex?

Sorry, I don't understand that. Can you link me to the specific test please.

SeasideSusie profile image
SeasideSusieRemembering in reply tohumanbean

No they don't, sorry, it's folate - brain and fingers not engaged. I'd just written a reply about leaving biotin off before a blood test and somehow typed biotin instead of folate in reply to you. You know the sort of thing! I blame it on the fact that I've not had anything for lunch yet, nothing to do with getting older and confused 🤣

humanbean profile image
humanbean in reply toSeasideSusie

I can empathise and sympathise. Typing the wrong word is becoming more and more common for me too, but I still miss a few of my mistakes.

TiredMummy profile image
TiredMummy

Thanks really helpful, thank you. I think I should take your advice and stop supplementation except for vit c and magnesium and get tested for zinc, copper, iron, vit d, b12, folate and selenium. But presumably I should get tested once I’ve been off supplementation for a while? Any idea of where I could get a test like this?

humanbean profile image
humanbean in reply toTiredMummy

I don't know who you intended to reply to, but you have, in effect, replied to yourself which is probably why you haven't had any replies.

To reply to a particular Reply you must click on the Reply button at the bottom of the post you are replying to.

The Blue Horizon blood test I linked to for SeasideSusie above (or below, depending on gadget) could be one that would be helpful to you.

bluehorizonbloodtests.co.uk...

humanbean profile image
humanbean in reply tohumanbean

TiredMummy

I forgot to answer this :

I think I should take your advice and stop supplementation except for vit c and magnesium and get tested for zinc, copper, iron, vit d, b12, folate and selenium.

There are differing opinions on how long you have to stop taking certain things. Personally I always stop (for a week) all supplements and medicines except the ones that would severely impact my health and quality of life by doing so e.g. pain killers, Holy Basil, 5-HTP - there may be others.

But I think the main advice on giving up supplements is :

When testing :

Iron, ferritin and anything else iron related, stop all supplements containing iron for a week before the blood draw.

Vitamin B12 - this takes so long to reduce (months or even years) that people usually just don't take it on the day of the blood draw.

Folate - Same as B12

Zinc and copper - I'm not sure. When I'm not sure I stop for a week before testing.

Magnesium - testing is not reliable, so I would never buy this as a single test or choose a particular test bundle because of a magnesium test being included. Since I get cramp, leg pain and insomnia if I don't take magnesium, I tend to keep taking it up to and including the day before the blood draw.

Vitamin C - Same as B12

Selenium - Same as Zinc and Copper

TiredMummy profile image
TiredMummy in reply tohumanbean

Sorry, suffering from hypo brain with the reply issues. Thank you for the info & link, most helpful

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