Iron intake and peripheral neuropathy. - Thyroid UK

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Iron intake and peripheral neuropathy.

Alejandrita17 profile image
26 Replies

Hi everyone,

I've been taking iron for a couple of weeks so that I can increase my ferritin (currently at 13). BUT my neuropathies have gone WORSE than ever (burning feet and skin, tingling in hands). Could these iron pills be the cause? Anyone with the same experience?

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Alejandrita17 profile image
Alejandrita17
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humanbean profile image
humanbean

What vitamin and mineral supplements are you taking right now?

Alejandrita17 profile image
Alejandrita17 in reply tohumanbean

B Complex, vit D and b12 (500 mcg x day).

Alejandrita17 profile image
Alejandrita17 in reply tohumanbean

PS. My b12 is 250 but MMA is ok. Nevertheless, i started taking 500 mcg x day. Vit D is 37, and i'm taking 2000 UI per day. I decided to supplement with B Complex too, since My neuropathies have become WORSE than ever after starting iron pills.

humanbean profile image
humanbean in reply toAlejandrita17

What are the units of measurement for your vitamin D?

Alejandrita17 profile image
Alejandrita17 in reply tohumanbean

Ng/ML. But i don't think vit D is the problem, since I've had it lower in the past without any problems. I suspect it's something iron-related.

greygoose profile image
greygoose in reply toAlejandrita17

I decided to supplement with B Complex too, since My neuropathies have become WORSE

It's absolutely essential to take a B complex when taking B12, because all the Bs work together and need to be kept balanced. :)

KellyDBrille profile image
KellyDBrille in reply togreygoose

I respectfully disagree regarding needing to take a b-complex. B6 can be toxic and cause neuropathy even at small, "normal" doses. This is often because folate is too low, but also sometimes B12. There's a webpage that goes back to 2007 (I think) where thousands have posted about nerve damage from B6.

greygoose profile image
greygoose in reply toKellyDBrille

You can get B complexex without B6.

SlowDragon profile image
SlowDragonAdministrator

How much levothyroxine are you currently taking

Improving low vitamin levels helps thyroid hormones work better/quicker often meaning you can get dose increase in levothyroxine

Low vitamin levels are directly due to being under medicated and still hypothyroid

When hypothyroid we frequently have LOW stomach acid, this leads to poor nutrient absorption and low vitamin levels as direct result

Low vitamin levels tend to lower TSH

Getting vitamins optimal frequently helps get next dose increase in levothyroxine

Alejandrita17 profile image
Alejandrita17 in reply toSlowDragon

Hi Slow Dragon,

I am currently on 75. My TSH is 1,9 which i assume is now ok. What i fail to understand is this: achieving better levels of vitamins and/or iron leads to an increase or a decrease un Levo?

SlowDragon profile image
SlowDragonAdministrator in reply toAlejandrita17

Just testing TSH is completely inadequate

75mcg is only one step up from starter dose

Which brand of levothyroxine are you currently taking

Do you always get same brand levothyroxine at each prescription

How long have you been on just 75mcg levothyroxine

You need TSH, Ft4 and Ft3 tested together

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/

Always test as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test

guidelines on dose levothyroxine by 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...

SlowDragon profile image
SlowDragonAdministrator in reply toAlejandrita17

Low vitamins are directly linked to being under medicated for thyroid

Great post about interconnection of iron and thyroid levels

healthunlocked.com/thyroidu...

Getting vitamin levels optimal improves symptoms

Also optimal vitamin levels improves conversion rate of Ft4 to Ft3

Obviously ferritin is dire and going to take a long time to improve ….many many months

Alejandrita17 profile image
Alejandrita17 in reply toSlowDragon

Hi Slow Dragon, here are my lastest results:

TSH: 177

T4:,1,4 (0,7-1,7)

T3: 2,58 (2-4,2)

Ferritin 14

Vit b12:950 (I think I oversupplemented!)

Vitd :52 (perfect)

Folate 15,50 (3-21)

Still having issues with my peripheral nerves. They told me T3 is ok, and that it can change a LOT intra day, so it's not a reference by itself. What do u think?

Thanks!!

tattybogle profile image
tattybogle in reply toAlejandrita17

TSH 177 ! .. i sincerely hope that's a typo ?

Alejandrita17 profile image
Alejandrita17 in reply totattybogle

1,77. Sorry

waveylines profile image
waveylines

The Symptoms you describe of burning and tingling are neurological and likely to be linked to your low level of b12. Even though it is in range its common for people with low levels like yours to exeprience these symptoms. The PA Society recommrnds everyones level should be over 500.

Its worth pointing this out to your GP but technically they dont have to treat unless you are under range EXCEPT if you have neurological symptoms they should not delay. Look up the guidelines they are on the PASociety website. Its important your GP doesnt delay treatment to avoid long term damage......many are not aware of the guidelines & are ignorant of treatment

MMA levels are not affected until much further down the line. GPs should not be waiting for the MMA to be affected. .

So your GP should check for the cause. Treatment is high level dosing of B12 -can be through supplements if you can absorb it or injections if you cant. 500 is a low dose for a supplement as you will only abosrbe a tiny fraction of what you take.

B12d.org have an excellant symptom checker that is well worth doing. Symptoms can be very wide. You need a good level of b12 for uptake and conversion of thyroid hormones too.

bookish profile image
bookish

Hi. Lots of things that might be going on here. You have started to take B12 for your likely- to- be- problematically- low B12, so the 'worsening' could be sensation returning to the damaged nerves as they begin to heal. This often happens with injections and larger oral doses but no reason why taking a relatively small dose wouldn't be able to do the same, especially if your need is great, which I suspect it is. We only absorb a fairly small proportion of each dose, so although I take a lot more B12 than you, I take it in split doses of about 500mcg at a time. You don't say what kind of B12 you are on - some suit one person better than another, and I use methylcobalamin because that works for me, so if this continues you could try a different one when you next run out. I found that although my neuropathy improved a bit and changed, I needed a small amount of methylfolate too (about 400 or 500mcg daily, which again I split into 3 doses) to actually make bigger improvements. It is quite possible that you, like me, have more than one thing affecting you. Iron being low or high can also cause neuropathy and presumably treating that could also cause 'healing' pain. Alternatively you might be reacting to a filler, or conceivably the iron itself which can raise histamine in some (as can many supplements) even though it is badly needed to help with histamine processing.

I know you said that you are not Coeliac, so I guess you have been tested, but low iron that you struggle to improve can be a sign of a gluten or other gut-affecting food intolerance or sensitivity, so I would encourage you to try a GF diet at least for a while. Coeliac testing misses a lot of people and gluten intolerance isn't looked for at all. This was an eye-opener for me and I started to absorb all kinds better once I quit the gluten (and dairy in my case).

You do mention taking a B Complex, so it would be worth checking how much B6 is in it. Some have high levels and some of us are more sensitive to B6, which can cause neuropathy both if too low or too high. My neurologist has found that some of his patients have really high B6 from using multis or complexes. If you are taking zinc, this can push copper down which can also cause neuropathy, so that's another one to be aware of. An anti-inflammatory diet generally may help and making sure that you are getting enough potassium (should be able to do with food, sweet potato, zucchini, quinoa etc) and magnesium, which I supplement with an oil spray on skin - very helpful for the nerve pain. Hope that helps. Best wishes.

humanbean profile image
humanbean

Vitamin D is 37 ng/ml

Actually, your vitamin D level is not that bad - the units of measurement with vitamin D make a huge difference to the interpretation.

37 ng/mL is equivalent to 92.4 nmol/L

The conversion in either direction can be done with this link :

grassrootshealth.net/?post_...

The optimal for vitamin D is variously quoted as 40 - 60 ng/mL or 50 ng/mL which is equivalent to 100 - 150 nmol/L or 125 nmol/L.

You can calculate what your ideal level of supplementation should be to raise your level to optimal and to maintain it there with this link :

grassrootshealth.net/projec...

...

Taking vitamin D raises the absorption of calcium from the diet. In order for that calcium to end up helping bones and teeth, rather than lining arteries, it is essential to take magnesium and vitamin K2.

SeasideSusie has written about these often so you could search for advice in her replies to others :

healthunlocked.com/user/sea...

greygoose has also written about magnesium, and possibly vitamin K2 as well.

healthunlocked.com/user/gre...

humanbean profile image
humanbean

My b12 is 250 but MMA is ok. Nevertheless, i started taking 500 mcg x day.

For someone with such a low level of B12 and who clearly absorbs it very poorly your intake of 500 mcg per day is actually quite low.

If your level hasn't risen significantly in the next 6 - 8 weeks then you could raise your dose substantially.

There are four different kinds of B12 available as supplementary forms but they are not all recommended. Please read this link carefully :

perniciousanemia.org/b12/fo...

Personally, I take a B Complex and a separate B12 supplement containing just methyl-B12. But I am thinking of switching to this one as recommended by SeasideSusie :

cytoplan.co.uk/vitamin-b12-...

humanbean profile image
humanbean in reply tohumanbean

Alejandrita17

I thought you might find this link of interest in terms of having a low B12 level.

stichtingb12tekort.nl/engli...

humanbean profile image
humanbean

I haven't seen a mention of folate (also known as vitamin B9) in this thread. If you haven't already come across this link it is worth reading :

chriskresser.com/folate-vs-...

I take methylfolate in a B Complex and also the occasional methylfolate in a separate supplement. I actually find that my folate levels never rise particularly high nowadays. They used to be higher some years ago because I took supplements containing folic acid, not methylfolate.

Folic acid is an inactive form of folate that the body must convert into an active form (of the type you find in food). Unfortunately it is quite common to find people who are hypothyroid who can't do that conversion very well. As a result the levels of folic acid in the blood may build up to quite high levels - but the body can't use it. Ever since I switched to always taking methylfolate my levels of folate in the blood have dropped dramatically, but I think it is actually a much healthier level now because I can use it.

The UK government has plans to fortify flour with folic acid. It might help a few pregnant (or planning to be pregnant) women but for anyone who can't process the stuff it isn't guaranteed to do much good.

The other thing about folate is that in order to make use of B12 in the body it needs adequate levels of folate. So for someone with B12 deficiency folate is essential too.

Mugs19 profile image
Mugs19

I have had a life long problem with iron supplements. While pregnant I had terrible pains in my feet. I was told it was a bit of gouty arthritis but years later when I was found to be anaemic the replacement iron caused the same pains in my feet, plus sinus irritation and motion sickness symptoms. More recently whenever I have tried to raise my ferritin levels with supplements I get muscle pains, usually in the top of my arms. Sometimes when I have eaten liver , I get strange pains. I don’t know what the answer is: possibly infusion?

humanbean profile image
humanbean

As for iron and your feet...

Which kind of iron supplement are you taking and at what dose?

Low iron/ferritin has more symptoms than most people are aware of.

drugs.com/mcd/iron-deficien...

thedailynutrition.com/iron-...

One thing to try is to wear warmer socks all the time, particularly in bed, because cold feet will make any foot pain worse. You could also wear woolly gloves or mittens when convenient.

Have you heard of haem/heme supplements and ferritin supplements? These are both different to iron supplements and are absorbed much more easily than iron. They also don't cause the gut problems that are so common to people taking iron. Helvella wrote a document about iron that is worth studying because it describes all the different kinds of supplements you can take.

dropbox.com/s/4d885frbic4z8...

Since your iron deficiency is so bad your body may have a lot of "housekeeping" and "repair work" to do which couldn't be done when thyroid and nutrient levels were low. So I agree with @bookish that you might be getting pain from healing.

...

Another cause of peripheral neuropathy is deficiency or toxicity caused by having too little or too much vitamin B6.

Deficiency : en.wikipedia.org/wiki/Vitam...

Toxicity : en.wikipedia.org/wiki/Megav...

A personal anecdote...

About 10 or 12 years ago I suffered from peripheral neuropathy. The pain was mainly in my feet. I started taking a high dose B Complex which included Vitamin B6 and over 2 or 3 months my feet stopped hurting. I then had a few months where I continued to take this B Complex and everything was fine. Then the pain in my feet started to come back. Luckily for me, some research made it clear that vitamin B6 is the only B vitamin that has the potential to cause toxicity problems. I stopped taking the B Complex I was taking and in a few weeks my problem went away again.

After that I spent a few years avoiding Vitamin B6 completely. When I restarted them I took products with very modest doses of B6 and I've had no problems since.

humanbean profile image
humanbean in reply tohumanbean

I just found this link on iron supplements and their side effects and it does mention tingling and numbness in the hands and feet as a known side effect. It could be pain caused by nerves healing.

healthprep.com/articles/med...

The link does mention the possibility of an allergic reaction if the numbness and tingling starts to affect your face, so that is something to be aware of and to look out for.

Alejandrita17 profile image
Alejandrita17

Thanks to all for your insights!

SlowDragon profile image
SlowDragonAdministrator

Vitamins are low because you are under likely under medicated on too low dose levothyroxine

75mcg levothyroxine is only one step up from starter dose

Ft3 is low

Request 25mcg dose increase in levothyroxine and retest in 6-8 weeks

Always test as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test

Meanwhile working on improving very low ferritin levels

Approx how much do you weigh in kilo

guidelines on dose levothyroxine by 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...

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