I had an appointment with my endo today and we talked about my sudden drop in T3 levels despite no medication decrease with the only change in my life being my weight gain and increased food and fibre intake. He said that both weight and diet can effect absorption which I knew was the case with levoythroxine but can this also be the case for T3? I always take my T3 1 hour before eating and 2 hours after last eating. I always take my t4 first thing alongside first lio dose and my levo level doesn't seem affected though over the last couple of months I am now having to take an extra 12.5mcg to achieve same level as previously. I calculated my fibre intake today and its about 33g a day (after previously having barely 10g when I had hypo gastroparesis and first started t3).
He has suggested an increase to 15mcg t3 and said I can split it 2/3 times a day as I feel works best. I am going to take the 3rd 5mcg in the evening before bed as my body likes t3 in smaller amounts and it occurred to me this will be about 4 hours after my last snack in the evening so is it possible that the last 5mcg could be absorbed at a greater rate due to being taken further away from food? I had always thought T3 was absorbed much more easily than T4 but now I am not so sure - of course my drop in levels could be due to other things but I was just curious if anyone knew of any ties between t3 absorption and fiber/diet?
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Although a high-fiber diet is usually recommended, too much fiber eaten right after taking thyroid medicines may interfere with their absorption. Wait two hours before you eat a high-fiber meal (one with more than about 15 grams of fiber).
There has not been much research into how foods etc affect T3 so little is known. We assume that it is best to use the same guidelines as we do for levo. The fact that you are having to increase your levo shows that something has changed and it has affected the working of your lio too and hence the suggested increase in dose.
5mcg is such a small dose of T3 that I don't think you would notice if it was being absorbed differently.
We each have to work out what suits us best timing wise with our food, supplements and medication dosing. I have always taking my levo in multiple doses too. I take 3 levo and lio doses the same time each day.
Thank you! I thought that was the case as I tried googling but can never find anything about T3! I will be interested to see if my bloods show a similar or bigger T3 level increase in 2 months!
Maybe these links will help. This Adviser to TUK (now deceased) had lots of helpful info to give. He'd never prescribe levo - only NDT (natural dessicated thyroid hormones )and T3:-
He himself became an expert in the use of T3 and had thyroid hormone resistance, which meant he had to take a dose of 150mcg daily in order for him to function. Not everyone has resistance to thyroid hormones. Dr Lowe also prescribed NDTs.
As your body starts to recover now that taking levothyroxine plus T3, it’s common to need to increase dose of levothyroxine or T3
Many of us need GOOD levels of Ft4 and Ft3
But only ever increase T3 or levothyroxine, not both at the same time
Getting bloods retested 6-8 weeks after adding this latest 5mcg T3 increase
Personally I find 3 small doses per day works best and 5mcg before bed helps improve sleep (Doses at 7am, 3pm and 11pm)
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 .
Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).
when also on T3, make sure to take last third or half of daily dose 8-12 hours prior to test, even if this means adjusting time or splitting of dose day before test
Come back with new post once you get test results
Important to regularly retest vitamin D, folate, B12 and ferritin too
Ah that is interesting as even though symptoms have returned due to lower T3 level I felt so much better like my body is recovering. I am quite happy to have a 3rd dose as when I have taken it at night in order to get in the 8-12 window before blood tests I too find I sleep better!
I am assuming you take T3 with a full glass of water, on an empty stomach and wait an hour before eating? I take mine when I get up, so stomach is empty.
I follow the method that Dr John Lowe used for his patients who took T3. This is an excerpt and he was an expert in the use of T3 as he took it himself. For other patients he prescribed NDT. An excerpt:-
"A trial of T3 therapy is then warranted.During the trial, the patient carefully progresses through met-abolic rehab using plain T3. The method of adjusting her dose of T3, and the safety monitoring she undergoes, are based on our experiences with hundreds of resistance patients and our scientific studies of those patients.[36][38][92][93][94][135][137][188][189][292][403] We want to emphasize that our patients use plain T3—not sustained-release or timed-release T3. They take their full dose of T3 on an empty stomach (one hour before a meal, or three hours after)once each day (see Figure 1).When thyroid hormone resistance patients use T3, therapeutic effects from a newly increased dose may occur within several days to a week. It’s reasonable for these patients to re-evaluate the inten-sity of their symptoms a week after they increase their T3 dose (seeChapter
3).We can’t give a specific starting dose for patients in general. Itvaries for different patients, depending on their health status, severity of their symptoms, and other factors. Many patients, however, start with what the clinician calculates to be a full replacement dose—one that provides all the thyroid hormone a normal thyroid gland would produce to regulate metabolism. The patient’s doctorshould help her calculate an appropriate starting dose.
From the starting dose, the patient gradually increases the thy-roid hormone at intervals that may vary from several days to aweek or two. She increases her dose based on her doctor’s calcula-tions; the amount of each increase is most often small. Gradually,through these increases, she reaches what we call her “therapeuticwindow”—the dose at which she has no symptoms of overstimula-tion, and her hypothyroid-like symptoms improve or disappear altogether.
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