I'm new to my diagnosis of hypothyroidism (Hashimoto's) and trying to understand a couple of things.
1. Can anyone explain why we should be aiming for TSH levels of <1 when the range is 0.55 to 4.78? I'd like to be able to explain to my doctor, since she seems to think that anything within range is "satisfactory".
2. Should I be getting T3 levels tested, and why does the NHS not provide this as standard if it's important?
The reason I ask is that, after being diagnosed with Hashimoto's 3 months ago and being put on 50mcg of Levothyroxine, my blood test results are now within range but I still have a lot of fatigue and weight gain. (I was tested early morning before taking Levo and on an empty stomach.) I've been increased to 75mcg of Levo, somewhat reluctantly, and will go back in 6 weeks for more tests.
For info, my results so far are below (these are NHS results - T3 not tested).
Mid-August:
TSH 9.57 mU/L (0.55 - 4.78)
Free T4 15 pmol/L (10 - 25)
FSH 43.0
Now (after 3 months on 50mcg Levothyroxine):
TSH 3.56 mU/L (0.55 - 4.78)
Free T4 16 pmol/L (10 - 25)
FSH 8.2
In Mid-August they also gave me results for:
Ferritin 42.4 ug/l (7.0 - 150.0)
Vitamin B12 344 ng/l (200 - 700)
Serum Folate 7.2 ug/l (3.0 - 20.0)
Thanks for your advice
Written by
Tatties
To view profiles and participate in discussions please or .
When we are on Levothyroxine dose should be increased slowly in 25mcg steps upwards until symptoms improve. For most people that means FT4 in top third of range and FT3 at least half way in range. Frequently TSH will be low
Official NHS guidelines saying TSH should be between 0.2 and 2.0 when on Levothyroxine
(Many of us need TSH nearer 0.2 than 2.0 to feel well)
With Hashimoto's we often have low vitamin levels. Getting vitamins optimal by supplementing can help improve conversion of FT4 to FT3
Have you had vitamin D tested?
What vitamin supplements are you currently taking?
Are you on strictly gluten free diet? Or tried it?
Bloods should be retested 6-8 weeks after each dose increase (or brand change)
Many people find Levothyroxine brands are not interchangeable.
Once you find a brand that suits you, best to make sure to only get that one at each prescription. Watch out for brand change when dose is increased or at repeat prescription.
Many patients do NOT get on well with Teva brand of Levothyroxine. Though it is the only one for lactose intolerant patients. Teva is the only brand that makes 75mcg tablet
Thanks slowdragon. Vit D was not listed in the results. I'm not taking any supplements currently but am starting a gluten free diet - shouldn't be a problem as I rarely eat bread and pasta anyway and can find substitutes for other foods I like.
I'm on 50mcg Levo from MercuryPharma and 25mcg from Teva. What should I be looking out for with Teva?
Can anyone explain why we should be aiming for TSH levels of <1 when the range is 0.55 to 4.78? I'd like to be able to explain to my doctor, since she seems to think that anything within range is "satisfactory".
Very, very few healthy people would have a TSH close to 4.78.
In healthy people their thyroids produce thyroid hormones in small amounts 24 hours a day - mostly T4 and some T3.
People with thyroid disease, who are being treated with extra thyroid hormones in pill form, have bodies which don't work the same way. They get a big dose of Levo, usually once a day. If they are lucky they may be taking T3 as well, and the same logic applies - they receive that T3 in big doses compared to continuous production of small amounts by a healthy body.
If a healthy person has a thyroid which produces, for some reason, a spurt of T4 or T3 which is slightly larger than normal for them their TSH production will be automatically adjusted downwards by a small amount to compensate. When thyroid hormone levels drop slightly the TSH is adjusted upwards. This compensation for small highs and lows goes on all the time. [In reality, TSH doesn't adjust as fast as T4 or T3 production, but over time it all averages out and the system works well for healthy people.]
A person with thyroid disease takes "big lumps" of T4 and/or T3 every time they take a thyroid hormone pill. These "big lumps" will usually drive the TSH down below what is normal for healthy people. It doesn't mean they are over-dosed. It just means that the body is doing what would be expected when presented with large amounts of thyroid hormone all in one go.
Unfortunately doctors think that having a low TSH means we are over-dosed or hyperthyroid, so they reduce the dose of thyroid hormones and make their patients suffer with a lot less actual thyroid hormones in their bodies all the time.
Two simple answers. The first is that the TSH range for patients on T4 is not the same as for healthy people. While the healthy range is about 0.5-4.4, for T4 therapy this range should be dropped to about 0.02-2. There are good physiological reasons for this which I won't go into here. The second point is that you are an individual and not a statistic. You personally have an optimum point in the TSH range which suits you. Though this fluctuates a little it does so in a far narrower range than that overall for everyone. Also of course FT4 and FT3 should be used in conjunction with TSH to give the full picture.
Thanks. I'm interested in the physiological reasons as I'm trying to educate myself - is there a paper or book on this that I might be able to understand as a lay person?
Should I be getting T3 levels tested, and why does the NHS not provide this as standard if it's important?
In an ideal world everyone would have their Free T3 measured every time they had a TFT - Thyroid Function Test. But the NHS wants to save money. It wants to save lots of money. So everywhere they can they scrimp and save and say NO where they can get away with it.
The NHS and the people who make the guidelines have been persuaded (or have persuaded themselves) that testing Free T3 is not necessary. A lot of the time they think testing Free T4 is not necessary either. And since many doctors don't have a clue about the symptoms of hypothyroidism they often won't test TSH either. One massive problem is that the majority of thyroid disease sufferers are women - and women are assumed to be anxious and depressed, and particularly anxious about their health, rather than being really ill. So we get fobbed off all the time. All we need is anti-depressants, allegedly. With some rare exceptions I would say the entire medical profession is sexist. Note that when men become hypothyroid they may get lumped in with women and some (but not all) of them end up being treated as badly as women. How stupid of them to get a "female" disease!
Going back to real life, rather than doctor's beliefs, and what patients have discovered for themselves...
Free T3 is a far better indicator of how well or ill a person with thyroid disease is. T3 is the active hormone required by every cell in the body.
Low Free T3 will give people hypothyroid symptoms.
High Free T3 will give people hyperthyroid symptoms.
TSH production though, is not guaranteed to tell anybody anything very reliably.
Getting Free T3 measured would be helpful for anyone with thyroid disease. But since doctors will rarely, if ever, measure Free T3 we are often forced to pay for the testing ourselves. (In the UK. I don't know how bad it is elsewhere.)
A personal anecdote : I was diagnosed with subclinical hypothyroidism and given my first prescription for 25mcg Levo when my TSH was just under 6, my Free T4 was about 15% of the way through the range, and my Free T3 was about 10% of the way through the range. I had to beg for it and my doctor was very angry with me for persisting. I had been told my thyroid was "borderline underactive" for the first time nearly 25 years before and had never been treated. I've been using this forum since 2013 and have seen quite a few people reporting results similar to mine and their TSH has been anything from well in range up to about 50. TSH is an absolutely rubbish measurement of thyroid function for me and many, many others. It just leads to life long poor health.
Thanks for the link. I had seen reviews of that book and intended to buy it but like so many things it vanished from my memory. I'll put it on my Amazon wish list to remind me.
Free T4 16 pmol/L (10 - 25) 40% of the way through the range
You haven't been prescribed enough Levo yet. Your TSH is far too high for someone to have a hope of feeling healthy. Your Free T4 is well under mid-range, which is also far too low for good health. Many people taking Levo need a level around 70% - 80% of the way through the range.
But you also need to know your Free T3 to have a complete picture of what is going on. You will probably have to pay for that yourself, sadly.
You can do anything from get just Free T3 tested (not recommended - instead, always get TSH, Free T4 and Free T3 done together from the same blood sample) up to getting a full Thyroid Function Test, thyroid antibodies, and some basic nutrients, or even get everyone single one of your vitamins and minerals tested if you had money to burn. It just depends on how much money you want to spend and whether or not it will be worth it.
One rule of thumb to consider...
Don't waste money on a test if you won't know what to do with the result or understand what it means or what to do with the result if it is over or under the range, or high or low in range, and don't know anyone who can help.
Also bear in mind that if you ever opt for a doctor's report on the results from the testing company (this is sometimes offered as part of the service for no extra cost), the doctors writing those reports are obliged to give the standard NHS advice, which usually boils down to "If it's in range, it's fine".
On this forum we have people who are good at interpreting results for thyroid-related results, basic nutrient levels, some are good with iron, some deal with saliva cortisol results. There is no real experience or knowledge on here of what to do with sex-hormone results (for example) which crop up on the forum quite often.
Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.
Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.
Increase needed but do I increase T4 or T3?
Please help me understand my blood tests. 
Help with understanding test results
Thoughts On Latest Blood Test Results Pls :)
Help comparing recent blood test to previous test 
