Vitamin B12 deficiency?: I have been feeling very... - Thyroid UK

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Vitamin B12 deficiency?

ctw0410 profile image
12 Replies

I have been feeling very unwell for about 3 weeks with dizziness, headaches, fatigue, weakness and in the last few days twitching muscles and blurry vision. Having hypothyroidism, I thought my levels must be out however my recent blood test (last week) suggests not:

TSH: 1.48 (0.30 - 4.20)

Ferritin: 19.9 (10-200)

Having researched my symptoms I wondered about a vitamin B12 deficiency? My Dr dismissed this possibility due to my Ferritin level being ok. Is she right? Does anyone have any idea what could be causing my symptoms and making me feel so unwell? Thanks so much.

(Currently taking 100mg of Teva Levothyroxine. Have been on this brand for over 12 months)

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12 Replies
Jazzw profile image
Jazzw

Do you have the laboratory reference ranges for your blood tests? Because if it’s the usual range for ferritin, that level is NOT ok. And ferritin and B12 aren’t related so your doctor said something really quite odd there!

Are you on levothyroxine? If so, how much? Did your doctor do any other thyroid tests, e.g., FT4 and FT3?

ctw0410 profile image
ctw0410 in reply to Jazzw

Thanks for your reply - just added ranges. I take 100mg of levothyroxine each day and no Dr only took TSH

SlowDragon profile image
SlowDragonAdministrator in reply to ctw0410

Approx how much do you weigh in kilo

Guidelines on dose by weight is approx 1.6mcg Levo per kilo of your weight

Even if we frequently don’t start on full replacement dose, most people need to increase levothyroxine dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until eventually on, or near full replacement dose

NICE guidelines on full replacement dose

nice.org.uk/guidance/ng145/...

1.3.6

Consider starting levothyroxine at a dosage of 1.6 micrograms per kilogram of body weight per day (rounded to the nearest 25 micrograms) for adults under 65 with primary hypothyroidism and no history of cardiovascular disease.

Also here

cks.nice.org.uk/topics/hypo...

gp-update.co.uk/Latest-Upda...

Traditionally we have tended to start patients on a low dose of levothyroxine and titrate it up over a period of months. RCT evidence suggests that for the majority of patients this is not necessary and may waste resources.

For patients aged >60y or with ischaemic heart disease, start levothyroxine at 25–50μg daily and titrate up every 3 to 6 weeks as tolerated.

For ALL other patients start at full replacement dose. For most this will equate to 1.6 μg/kg/day (approximately 100μg for a 60kg woman and 125μg for a 75kg man).

If you are starting treatment for subclinical hypothyroidism, this article advises starting at a dose close to the full treatment dose on the basis that it is difficult to assess symptom response unless a therapeutic dose has been trialled.

BMJ also clear on dose required

bmj.com/content/368/bmj.m41

bestpractice.bmj.com/topics...

Guidelines are just that ....guidelines.

Some people need more …..some less

healthunlocked.com/thyroidu...

ctw0410 profile image
ctw0410 in reply to SlowDragon

I'm about 61kg so I think according to the calculations dose sounds about right

SlowDragon profile image
SlowDragonAdministrator in reply to ctw0410

So you can’t use guidelines to push for dose increase….if test results show you are under medicated

Getting all four vitamins tested and to optimal levels can significantly improve symptoms

Ferritin currently likely causing significant fatigue

Come back with new post once you get full results

SlowDragon profile image
SlowDragonAdministrator

Just testing TSH is completely inadequate

Ferritin looks extremely low. Any ferritin result under 30, GP should be doing full iron panel test for anaemia

Please add ranges on results

How much levothyroxine are you currently taking

Do you always get same brand levothyroxine at each prescription

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested.

Also EXTREMELY important to test vitamin D, folate, ferritin and B12

Low vitamin levels are extremely common, especially with autoimmune thyroid disease (Hashimoto’s or Ord’s thyroiditis)

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

Is this how you do your tests?

Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins

List of private testing options

thyroiduk.org/getting-a-dia...

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins by DIY fingerprick test

bluehorizonbloodtests.co.uk...

Thriva Thyroid plus antibodies and vitamins By DIY fingerpick test

thriva.co/tests/thyroid-test

If you can get GP to test vitamins and antibodies then cheapest option for just TSH, FT4 and FT3

£29 (via NHS private service ) and 10% off down to £26.10 if go on thyroid uk for code

thyroiduk.org/getting-a-dia...

monitormyhealth.org.uk/

NHS easy postal kit vitamin D test £29 via

vitamindtest.org.uk

If TPO or TG thyroid antibodies are high this is usually due to Hashimoto’s (commonly known in UK as autoimmune thyroid disease).

About 90% of all primary hypothyroidism in Uk is due to Hashimoto’s. Low vitamin levels are particularly common with Hashimoto’s. Gluten intolerance is often a hidden issue to.

Link about thyroid blood tests

thyroiduk.org/getting-a-dia...

Link about Hashimoto’s

thyroiduk.org/hypothyroid-b...

List of hypothyroid symptoms

thyroiduk.org/if-you-are-un...

SlowDragon profile image
SlowDragonAdministrator

Ferritin is far from OK!

Iron and ferritin often low when hypothyroid, especially if under medicated

See/contact GP and request they do full iron panel test for anaemia

Meanwhile

Look at increasing iron rich foods in diet

Eating iron rich foods like liver or liver pate once a week plus other red meat, pumpkin seeds and dark chocolate, plus daily orange juice or other vitamin C rich drink can help improve iron absorption

List of iron rich foods

dailyiron.net

Links about iron and ferritin

irondisorders.org/too-littl...

davidg170.sg-host.com/wp-co...

Great in-depth article on low ferritin

oatext.com/iron-deficiency-...

drhedberg.com/ferritin-hypo...

This is interesting because I have noticed that many patients with Hashimoto’s disease and hypothyroidism, start to feel worse when their ferritin drops below 80 and usually there is hair loss when it drops below 50.

Thyroid disease is as much about optimising vitamins as thyroid hormones

healthunlocked.com/thyroidu...

restartmed.com/hypothyroidi...

Post discussing just how long it can take to raise low ferritin

healthunlocked.com/thyroidu...

Never supplement iron without doing full iron panel test for anaemia first

Posts discussing why important to do full iron panel test

healthunlocked.com/thyroidu...

healthunlocked.com/thyroidu...

Iron/ferritin and restless legs

healthunlocked.com/thyroidu...

Helpful post about iron supplements and testing

healthunlocked.com/thyroidu...

Also essential to regularly retest vitamin D, folate and B12

SlowDragon profile image
SlowDragonAdministrator

Suggest you print this out and have to hand when talking to GP

cks.nice.org.uk/topics/anae...In all people, a serum ferritin level of less than 30 micrograms/L confirms the diagnosis of iron deficiency.

ctw0410 profile image
ctw0410 in reply to SlowDragon

Thanks so much - really helpful

Mrshappyme profile image
Mrshappyme

hello i would ask your doctor to do some vitiman s test i had vitiman d3 leavel 15 i was so ill . i now take vitiman d3 every day 1000 iu per had . you need to have some vitiman test hope you feel better soon .

SlowDragon profile image
SlowDragonAdministrator in reply to Mrshappyme

With vitamin D so low you should have been prescribed LOADING dose vitamin D…..that’s 300,000iu in total over 6-8 weeks

Followed by ongoing maintenance dose, Likely to need higher dose than 1000iu daily

Retest twice year

Vitamin D mouth spray by Better You is very effective as it avoids poor gut function. There’s a version made that also contains vitamin K2 Mk7

amazon.co.uk/BetterYou-Dlux...

It’s trial and error what dose we need, with hashimoto’s we frequently need higher dose than average

Calculator for working out dose you may need to bring level to 40ng/ml = 100nmol

grassrootshealth.net/projec...

Vitamin D and thyroid disease

grassrootshealth.net/blog/t...

Mrshappyme profile image
Mrshappyme

hello ctw0410 did you find out what is causing your syntoms i was woundering if it was vitiman d3 .

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