Thyroid UK

Can someone help me out who knows about basal body temperature and how it translates to symptoms?


I'm going to the dr tomorrow for a 6 week review as fairly early into my diagnosis.

I had bloods back last week and here are my before and after results.

Before T3 2.1 after T3 5 (3.5-7)

Before t4 10.2 after t4 16 (12-23)

Before tsh 1.4 after tsh 0.96 (0.1-5)

My symptoms have got much better but I do feel like I want a dose increase but not sure if the dr will do that based on my bloods. I bought a digital thermometer and took my temperature and it's 35.4... Isn't that quite low still? Should I tell my dr that? Will he understand? I'm scared they won't put up my medication because my tsh is going low and they get scared of hyper...

Any help or advice on the body temperature thing would be great

12 Replies

Take your temperature every day for at least a week. It should be done first thing in a morning before you get out of bed. Your temperature should be above 36.5. anything below that can indicate hypothyroidism if symptoms are present.Your FT3/ FT4 test results are still only mid-range and most people feel better at the top of the range.

Take your temperature results to your doctor by all means but I have found that most of them do not know about the Basel temperature test and hence will not acknowledge that you are showing them anything of significance. Good luck!


If your doctor can see beyond your TSH, there is room for an increase. Dr Toft says that your FT4 and FT3 should be in the top 25% of the reference range, so you've got a bit to go yet.

As for your temp, yes, it's better to get more than a couple of days data, but as lynn says, you'll be lucky if this means anything to your GP.

I've been on levo since June and only now is my temperature starting to rise. In the last three weeks it has been consistently 36.0 or above (but no higher than 36.3). Either way it's a lot better than the 34.5s I used to get and I take it has an indication that things are generally on the up and this is catching up with everything else.


Thank you....luckily he can see beyond my TSH...see below :)


Before the thyroid gland blood tests came in, the Basal temp test was used as well as clinical symptoms to diagnose. I doubt GP's today would take notice of the Basal temps.

Also for info:-


Hi, your results look similar to mine, although my T3 is within range and my TSH has been lower. My average waking temperature has been 35.4. I'm 3 weeks into a trial of thyroxine, have been experiencing symptoms for years. Out of interest what were your symptoms before the medication?

I had to explain the Basal temperature to my GP, she was very interested and told me to let her know what happens to my temperature.



my symptoms before were:

extreme fatigue after doing anything strenuous, constipation (went once every 3/4 days) feeling really spaced out/brain fog, cold and hard to warm up - I had a back massage for an hour and the therapist said i'm the first person whose back she hadn't managed to warm up!- hair never grew, periods stopped, couldn't lose weight no matter what I did- despite extreme calorie counting/exercise etc- needed regular naps and found it hard to get through the day without them- just never feeling rejuvenated even with 10-12 hours of good sleep. just EVERYTHING was a struggle, life just had a cloud over it all of the time.

The first couple of weeks of thyroxine were really hard but now I can say the brain fog has all but gone, I have more energy, I visit the toilet twice or three times daily (massive change!) my period started after 5 weeks, and the colour is slowly coming back to life. I just had an intense set of university exams (I'm in my final year) and I was revising constantly and only sleeping from about 2am-7am and I managed to get through this. Before I was diagnosed at University I couldn't concentrate on studying for longer than half an hour!

Hope this helps :)


It can take time for all body functions to recover but have they tested








without all of those above middle of their ranges your body will sttill struggle to work properly


all of these have been tested I believe and because I'd been taking supplements for a while all were good and B12 and D3 were above the range. The only slightly low one is ferritin at 60 but upon your recommendation I'm taking spatone daily so this should start to get better. My ferritin 2 years before was only 11 so it has come up a lot. Do you think the spatone is sufficient for me at the moment?


Hi, I'm sorry but most dr.'s don't seem to think temp to be the slightest bit important. My temp has not been taken by a dr. or specialist in 25 years. In days long gone, it was the first thing they did-not any more. When I mentioned my morning temp of to the dr. (32-34cc) Hesaid "the body does funny things" All the best for today


Hi everyone, thanks for your replies. I actually cannot believe how fantastic my new Dr is. I joined a new surgery when I came back for my final year of University and had 2 terrible GPs who would only focus on the TSH and said it's impossible for me to have a thyroid problem if my TSH is between 1 and 2. I then had to pay privately to find out my free T3 and free T4 were as low as they were as you can see!

finally went to another and he has been so good. I started on 50mcg and he agreed after 6 weeks to ensure my free T3 and free T4 are always checked because for me, my TSH is not an indicator. And indeed, after 6 weeks this was done, and he has said it will always be done for me. I think he has daughters at university so maybe empathises with my situation and identifies with me.

Anyway, I didn't even need to mention the temperature thing today because he said exactly what you guys have said -'Your levels are now in the normal range, but the normal range is big, so there is no one right dose for you and we might as well try you on the biggest dose you can be within normal and not go over'. and he asked what I wanted and what I felt. It just felt amazing to be able to sit there and talk to someone who actually wants to work with you. I obviously want to increase my dose and we discussed that it would be good to try 75mcg so I'm in effect increasing my dose by 50% rather than 100% which could be too much at once.

Then I'm going to have another blood test in 6 weeks and as long as I'm not over or maxing the range we will increase to 100mcg. I urge anyone having problems with GPs to keep looking, I was at such a low with one of mine. I think it's about clicking with someone and establishing a relationship so it's not a battle. WE already have a battle on our hands with thyroid everything else has to be as smooth as can be.

Thank you for all your help again,


It will still take time and patience for everything to get back on track

usually they say 9 months

but everyones body is different as are their lifestyles


Glad things are going well for you. Just a small point - I understand you will only become hyper when the FT3 is high/above the range....hope all goes well in your final year....


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