Thyroid levels fluctuating - not taking medication

[Bfarliegh]

hi

I am curious whether 'normal' thyroid levels fluctuate in people who are not medicated?

I ask as 2 years ago by Free t4 was 18nmol (12-22) and now it is 21.4 nmol (12-22) and I was wondering if this is normal?

many thanks for any input

[eeng]

Thyroid hormone levels can fluctuate quite a lot, especially for people who have thyroid antibodies (there are at least 2 types). Other factors affecting T4 levels probably include time of day, diet, activity levels and time of year (sounds odd but many people need more FT4 during the winter months - my theory is that your metabolism needs to work harder to keep you warm in winter as well as your normal activity).

This is why doctors shouldn't just dose us according to our blood test results but according to our symptoms. Sadly they rarely do these days.

However if your FT4 continues to increase above the normal range you should look out for symptoms of hyperthyroidism, which is something I have no experience of and is apparently very unpleasant.

[Bfarliegh in reply to eeng]

Thanks so much for the info. Really appreciate it. I am learning so much!!