so grateful for comments as so much to learn
So optimal levels - obviously slightly different for everyone but as a guide
THS should be 2-2.5 or 1.5-2.5
Vitamin D 100
What are other optimum levels please ?
I have added blood results when I came off levothyroxine and started again after about 2 weeks on 100 - I will stay on 100 now and get new bloods in 6 weeks. So grateful to have found this site x
A TSH of 2.5 would be much too high for the majority of people on thyroid hormone replacement. Most need it at 1 or under - often under-range, especially if taking T3.
Even so, TSH level doesn't always correspond to thyroid status once it gets down to 1, because it's not the TSH that causes symptoms. It's the FT3 level that is most important, and they rarely even test that. It's T3 that causes symptoms when it's too high or too low. And most hypos need it around the 75% through the range.
TSH should be under 2 as an absolute maximum when on levothyroxine
gponline.com/endocrinology-...
NHS England Liothyronine guidelines July 2019
sps.nhs.uk/wp-content/uploa...
Page 9
Test for Deficiency of any of the following: Vitamin B12, Folate, Vitamin D, Iron
See page 13
1. Where symptoms of hypothyroidism persist despite optimal dosage with levothyroxine. (TSH 0.4-1.5mU/L)
Graph showing median TSH in healthy population is 1-1.5
web.archive.org/web/2004060...
Comprehensive list of references for needing LOW TSH on levothyroxine
healthunlocked.com/thyroidu....
LEVO DOSE SHOULD NOT BE DETERMINED BY TSH
Diogenes/Toft paper:
bmcendocrdisord.biomedcentr...
healthunlocked.com/thyroidu...
The link between TSH, FT4 and FT3 in hyperthyroidism is very different from taking thyroid hormone (T4) in therapy. In hyperthyroidism, FT4 and FT3 are usually well above range and TSH is very low or undetectable. In therapy, FT4 can be high-normal or just above normal, TSH can be suppressed but FT3 (the important hormone that controls your health) will usually be in the normal range. FT4 and TSH are of little use in controlling therapy and FT3 is the defining measure. A recent paper has shown this graphically:
Heterogenous Biochemical Expression of Hormone Activity in Subclinical/Overt Hyperthyroidism and Exogenous Thyrotoxicosis
February 2020 Journal of Clinical and Translational Endocrinology 19:100219
DOI: 10.1016/j.jcte.2020.100219
LicenseCC BY-NC-ND 4.0
Rudolf Hoermann, John Edward M Midgley, Rolf Larisch, Johannes W. Dietrich
LlINK TO PAPER:
Hello there :
I now aim for a ferritin at around 100 ; folate around 20 ; B12 active 75 ++ ( serum B12 - 500++ ) and vitamin D around 100 : ( Based of Medicheck blood test ranges )
As a rule of thumb aim to be at least 50% through the ranges -
ranges vary from Lab to Lab so always detail them when you share your blood test results.
Your TSH, when optimally medicated will likely be low in the range and likely under 1 :
T4 - Levothyroxine is basically inert and a storage hormone which needs to be converted in your body into T3 the active hormone that runs all your bodily functions and it is too low a level of T3 for you that causes the symptoms of hypothyroidism - just as too high a level of T3 for you would cause symptoms of hyperthyroidism.
When on T4 monotherapy we generally feel best when the T4 is in the top quadrant of its range as this should convert to a decent level of T3 at around a 1/4 ratio - T3/T4 :
Sarahpoppe232
When talking about optimal vitamin levels, we have to remember that some of the key nutrients have more than one unit of measurement and what is optimal with one unit of measurement would be totally incorrect for another.
For example, Vit D can be measured in nmol/L (the more common one in the UK) or ng/ml (more common in the US but is used in some parts of the UK).
The recommended Vit D level, according to the Vit D Council, Vit D Society and Grassroots Health, is
100-150nmol/L or
40-60ng/ml
and Grassroots Health's recent blog post recommended at least 125nmol/L (50ng/ml).
So you can see how important it is to know the unit of measurement before stating the optimal level.
Similarly for folate but with folate it's the reference range which varies. On the forum, and with the private labs and NHS labs we see:
>2.89
>3.89
2..9-14.5
3.89-19.45
The above ranges have been seen with Medichecks when they use County Pathology to process the tests.
8.83-60.8 is used by Medichecks when they use INUVI to process the tests, also Blue Horizon and Thriva.
So we must know the range to suggest the optimal level, we can't just say 20.
Folalte is recommended to be at least half way through range so for the first 2 ranges mentioned above double figures is suggested so upper teens to 20 would be OK.
For 2.9-14.5 then half way through would be 8.75 so that would be the very least to aim for.
For 3.89-19.45 then your looking at at least 12.
For 8.83-60.8 then you're looking at at least at least 35.
And for these latter 3, as you have an upper limit of range, anywhere between half way and top of range is said to be acceptable.
I think folate is very confusing because all the ranges seem to have the same unit of measurement so presumably it's down to how they calibrate their machine, so it's essential to look at the range.
If Active B12 is measured then according to Viapath at St Thomas' Hospital:
viapath.co.uk/our-tests/act...
Reference range:>70. *Between 25-70 referred for MMA
So below 70 should be tested for B12 deficiency. We tend to suggest 100 plus for Active B12.
If Total B12 is measured, again there are two units of measurement - pg/ml (or ng/L which is the same) and pmol/L. The reference ranges vary quite a bit so again it's important to know which range has been used. Typical ranges are:
pg/ml or ng/L - 197-771 or 150-900 (they are the latest ones I've seen).
pmol/L - 145-569
According to an extract from the book, "Could it be B12?" by Sally M. Pacholok:
"We believe that the 'normal' serum B12 threshold needs to be raised from 200 pg/ml to at least 450 pg/ml because deficiencies begin to appear in the cerebrospinal fluid below 550".
"For brain and nervous system health and prevention of disease in older adults, serum B12 levels should be maintained near or above 1000 pg/ml."
So for pg/ml or ng/L the level quoted above would be appropriate. If the unit of measurement was pmol/L it would have to be converted to pg/ml and this is done by multiplying by 1.355. For example, if the level was 450pmol/L then that would be 609.75pg/ml.
For Ferritin half way through range is sometimes suggested but with so many ranges there can be a big difference. Ranges we see here are
13-150
30-300
and INUVI lab (one of Medichecks' labs) they use
Males 16-60: 30-400 ug/L
Female's: 16-60: 30-150
Both if over 60 years of age: 30-650
And some experts say that the optimal ferritin level for thyroid function is 90-110ug/L.
wow brilliant thanks - I will print this out
Folate: Optimum Levels Advice?
Optimum levels of t3/t4?
Optimum thyroid levels? 
Optimum level T4.T3
Help Interpreting Vitamin Levels
