My doctor has previously told me that I have a slightly underactive thyroid. This was about two years ago. She had me re-tested and told me that I was a bit borderline and didn't need medication. However it seems to be on my records that I have underactive thyroid, as a Dr in another situation commented on it.
I am trying to lose weight on a very low carb (virtually keto) diet and as progress is slow I am wondering if my thyroid issues might be affecting me.
I don't actually know anything about thyroid issues as such and would value a perspective on this. Thanks, LondonSue
A good starting point would be to get hold of your last blood tests and see what was actually tested, and what the results are. You are legally entitled to the blood results, without giving a reason for wanting them, but it's often easiest to say "for my records" when asked.
I expect they have only tested TSH, which is wholly inadequate, or if you are very lucky free T4. TSH, thyroid stimulating hormone, is a message from the pituitary to tell the thyroid to do more, if it is struggling and not making enough thyroid hormone. The more it struggles, the higher the TSH goes. A healthy euthyroid person would not have a TSH reading of more than 2, and often less than 1. The thyroid then produces free T4, an inactive hormone, which converts into free T3, the active thyroid hormone needed in every cell of your body. You need both of these to be high in range to feel well (and, in my experience, to have any chance of losing weight). It is absolutely not good enough to be told your results are "normal" or "in range" - it's where you are in the range (which varies from lab to lab) that matters.
Ideally you would have full thyroid testing - ie TSH, free T4, free T3, thyroid antibodies and key nutrients - ferritin, folate, vit D and B12, as your thyroid is happiest when these are all nice and high. If your GP can't or won't test these, you will see lots of posts here about private testing - and there are usually discounts available on the Thyroid UK site or - as the next post shows - with Medichecks on Thursdays,
Thank you! I have also been reading that low carb /keto can also interfere with thyroid function so I need to get informed!! I have to dash out and do my grocery shopping but will be back later! Thank you for this info.
You need a certain amount of calories for your thyroid to work properly -but some people find low carb/keto is ok. I think the carbs in veg etc is important- you need lots of leafy veg to keep your folate high. You must avoid any supplements etc with added iodine - and also need to avoid soy, and shakes etc which contain soy if you are hypo.
You need carbs to convert T4 to T3. So, whilst it wouldn't affect your thyroid function, a keto diet could leave you with low FT3. But, this varies in degree from person to person.
If you are over-weight, that is probably due to your under-active thyroid. You should know that doctors will do and say anything to avoid diagnosing and treating hypothyroidism. The fact that she says you are 'slightly under-active' or 'a bit borderline' (!!!) doesn't mean it is so. Being hypo is like being pregnant: either you are or you aren't.
This is why we always, always need to get a print-out of our blood test results. We need to know exactly what was tested and exactly what the results were. And keep our own records.
What you say is absolutely true....I'm going through this right now. I went on a SUPER low carb diet because I had VERY high fasting insulin.......in other words, I was just about to tip over into diabetes. I have managed to lower both my fasting insulin from 24.9 to 16.2 in three months, although I still have a way to go. It would appear that this kind of aggresive dietary aproach is the only thing that is showing results on my insulin levels. BUT...on the other hand....as you said.....my T3 has dropped and my TSH and T4 have gone up......half measures just don't seem to work for me......ie if I just ease on the diet and add a few more carbs in.....my insulin will not budge !!
TSH 3.93....... ref 0.27 - 4.2
Free T3 3.4........ ref 3.1 - 6.8
Free Thyroxine 16.9........... ref 12 - 22
Thyroglobulin ab 10.1......... ref 0 - 115
Thyroid Peroxidase ab 25.8......... ref 0 - 34
Folate 4.8 .........ref > 2.9
Vit B12 active 120........ ref 25.1 - 165
Vitamin D 146 ............ref 50 - 200
Ferritin 142 .................ref 13 - 150
CRP HS 4.8........... ref 0 - 5
Previous to this my TSH had been below 1 for a long time........This is causing me quite a bit of anxiety at the moment as I don't know whether to ease off the diet and have my insulin lowering stalled but restore......maybe.....some of my thyroid levels.
Sorry my latest TSH...on 17/09 was 21.9.......ref 12 - 22 pmol/L this is NHS test and reference. The list above is from Medichecks .....they seem to have different measuring and ref ranges
First thing is, do you have any actual blood test results? if not will need to get hold of copies.
You are legally entitled to printed copies of your blood test results and ranges.
The best way to get access to current and historic blood test results is to register for online access to your medical record and blood test results
UK GP practices are supposed to offer everyone online access for blood test results. Ring and ask if this is available and apply to do so if possible, if it is you may need "enhanced access" to see blood results.
In reality many GP surgeries do not have blood test results online yet
Alternatively ring receptionist and request printed copies of results. Allow couple of days and then go and pick up.
Important to see exactly what has been tested and equally important what hasn’t been tested yet
For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12
Low vitamin levels are extremely common, especially if you have autoimmune thyroid disease (Hashimoto's) diagnosed by raised Thyroid antibodies
Ask GP to test vitamin levels and thyroid antibodies if not been tested yet
Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)
Private tests are available as NHS currently rarely tests Ft3 or thyroid antibodies or all relevant vitamins
Lot's of great info thank you. I am low on Vit D which I know is common. I feel ok in myself and don't have any particular issues other than worrying it is affecting my ability to lose weight and I want to do this for my health esp at age 56. I am carrying a lot of extra stone. Always been a carb lover with a sweet tooth!! 🙄🙄 Thyroid issue just showed up in recent years.
I am wondering does carrying extra weight contribute to under active thyroid? I mean over the years...? Is that why I have it?
But come back with new post once you get results from GP
Then members can advise on next step
Hi sue omg 2 years you were left before they can actually re test you is appalling. I was told after a borderline result they have to test 6 weeks after and if it’s still borderline or higher they try you on thyroxine medication. I had another dr told me it’s 3 months before your tested and then they decide if you need medication so it’s all down to their own personal opinion and not medical fact as no one can agree. I too have tested positive for under active thyroid too at borderline level. I can’t lose weight I have now given up. I explained that I have been treated for under active thyroid for 20 years by a alternative therapist but I haven’t been lately and am piling on the weight. I think that they have a duty of care to give you some medication to see if it makes a difference. I can’t believe they just left you till now but they are just so lax. I think it’s worth going back to the drs and ask for more information and a copy of all your blood tests for thyroid then ask them to take you through the results if it’s constant then they should give you a definite diagnosis and a treatment plan. I really do hope they explain everything to you as you have a right to know. Good luck with the dieting and getting answers. Have a lovely evening. Take care. J xx
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