Daily Rhythms of Thyroid Hormones + TSH - Thyroid UK

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Daily Rhythms of Thyroid Hormones + TSH

helvella profile image
helvellaAdministratorThyroid UK
13 Replies

Over ten years ago, I first posted about the daily rhythms of TSH, Free T4 and Free T3.

For reasons I do not know, later, updated posts no longer exist. (The original is still available but I had improved it in the later versions.)

Not at all unhappy about this, just perplexed. The reason being Tania at Thyroid Patients Canada has done two excellent and far more comprehensive posts. Much better go there . :-)

The significance of the TSH-FT3 circadian rhythm

By thyroidpatientsca on July 31, 2020

thyroidpatients.ca/2020/07/...

Circadian rhythms of TSH, Free T4 and Free T3 in thyroid health

By thyroidpatientsca on July 31, 2020

thyroidpatients.ca/2020/07/...

[Just for reference, the ten-year-old post is here: healthunlocked.com/thyroidu... ]

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helvella profile image
helvella
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gabkad profile image
gabkad

Thanks for rabbitholing me. I started reading the other stuff on that site and I'm doing my best to not get upset. I'm giving this a break and will resume reading tomorrow. Thanks.............going out to check on my allotment and see if I need to water. It's 28C and disgusting

out there.

HighlandMo profile image
HighlandMo

Can this be simplified??? I’m sure it’s interesting but I can’t get my head around it.

helvella profile image
helvellaAdministratorThyroid UK in reply to HighlandMo

The simple interpretation is this:

TSH varies through the day, significantly. Enough that a blood test taken at one time of day might indicate the need for treatment, but a test with blood drawn at a different time of day would be viewed as not indicating need for treatment.

The difference between high and low varies one individual to another.

FT4 and FT3 do vary, but not nearly as much as TSH.

HighlandMo profile image
HighlandMo in reply to helvella

Thank you. That’s easier to understand!

jendwall profile image
jendwall in reply to helvella

Does any of this info suggest that the time we take our meds, esp. T3 meds, matters to our circadian rhythm? For example, would it be better to take T3 before bed or in the middle of the night? Most seem to take T3 in the morning, and many divide that morning T3 dose with other doses during the afternoon.

helvella profile image
helvellaAdministratorThyroid UK in reply to jendwall

Yes.

I have always taken my levothyroxine at bed-time. Although T4 levels do not change that much, I did choose this partly because it seemed likely to be slightly closer to the rhythm we usually have.

It is difficult to be certain without comprehensive testing as some people have much flatter rhythms than others.

jendwall profile image
jendwall in reply to helvella

So what time of day is best to take T3 so it coincides with our natural rhythm?

helvella profile image
helvellaAdministratorThyroid UK in reply to jendwall

I think I'd rather let those who take T3 answer!

I do know that some take some or all their T3 at bed-time - but that others do not.

jendwall profile image
jendwall in reply to helvella

according to the links, it made me feel like it said that T3 seems to naturally drop in the morning, which doesn't make sense to me, unless cortisol is the thing that's supposed to get us going when we wake up in the morning? Just trying to understand the research article, lol.

helvella profile image
helvellaAdministratorThyroid UK in reply to jendwall

I really do think that the idea T3 stimulates is wrong. It doesn't get us going - it is necessary for us to get going but it is not like coffee - or whatever.

In my view, adequate thyroid hormone is essential for sleep - for our bodies to recover, and get ready.

Many point at the fact that in hypothyroidism our body temperature tends to be a bit lower. Which highlights the link between temperature and thyroid hormone. But if you think about it, you need that extra during the night when you are inactive. That warmth is essential for good, refreshing sleep. Upon rising, your activity will help keep you warm. So T3 dropping in the morning makes lots of sense.

NWA6 profile image
NWA6 in reply to helvella

Agree for sure that it’s not a stimulant, it’s not coffee and I wish our uneducated medical staff would stop thinking that it is coffee 😩

T3 definitely doesn’t stimulate me. Quite the reverse. Makes me sleepy and feels like a medicinal cosh if taken in the day no matter how tiny a dose. But it does make me feel calmer and less anxious (which might just be because I feel more capable in managing life - at the moment anyway. Who knows what tomorrow will bring).

jendwall profile image
jendwall

Thank you for the interesting feedback. I can say that I frequently go back to sleep after taking my Levo and T3 in the morning. Usually no problem falling back to sleep at all.

Coffee does nothing for me in the morning, but keeps me up if I drink it too late in the afternoon on, lol.

The heat thing is another story when female hormones are at play. Definitely don't need help staying warm overnight right now. :)

I have experienced being really cold in the evening/overnight, though, when I was hypo/ undermedicated. It was horrible. The best thing my doc suggested was to warm up the feet area under the covers with a heated throw blanket, and then remove when going to bed. Once my levels stabilized, I no longer struggled with being cold.

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