NDT and weight gain??

Hi everyone, I am just wonderingif anyone has any experience of gaining weight since starting NDT?

All the posts I read seem to suggest that people loose weight once starting NDT. I have been on it for almost 12 months, and I seriously can't handle the weight issue, I have put up almost 28lbs since starting 😒I take 3 grains of Nature Thyroid.

I am seriously considering going back on levo 200mg and adding T3??

Has anybody done this?? 😊

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Weight gain may indicate you are under medicated or perhaps thyroid meds aren't being utilised properly (ie administering the correct dose but it is failing to be become biologically active) ?

You said you were feeling grumpy in a post a month ago which may indicate hormonal imbalances .

Do you have recent thyroid hormone test results ? .. Are your iron//nutrients really OPTIMAL ? ? ..

The ratio of T4//T3 in NDT isn't right for everybody and it may be that you need to add a little something extra. Post any results complete with ranges (numbers in brackets) for members to comment.

Hi the only results I have are the last ones posted, I am due for bloods again in 4 weeks.

I am taking 3 grains in the afternoon, away from all other medication, coffee, supplements etc

I take B12 methacoblamin 1000mg and also vitamin d, and iron x


It is the T3 that is the biological hormone and very powerful. You could try splitting your dose to reduce the rapidity of onset and prolong the duration of its action.

I take my first dose at about 6am and second 3-4pm.

Weight gain can also be down to blood sugar issues (insulin resistance) when we have too much T3.

Also high cortisol levels, which will put fat around the middle waist area.

I was diagnosed with insulin resistance a few years ago, after failing to lose weight even on NDT. The doctor wanted me on Metformin, but I chose a supplement instead: berberine (available OTC), 500 mg, taken with all main meals. Since going on it, I have lost 27 kilograms pretty effortlessly. My fasting blood sugar and insulin levels are now close to the lower normal limit (before berberine, they were close to the upper normal limit).

Insulin is a fat-storing hormone and can make weight loss very difficult or even impossible. It might be worth having your fasting blood sugar and insulin levels checked if you have not done so already.

My own experience is that people who have lived with hypothyroidism for a long time, and then been inadequately treated with T4 only drugs, can have a lot of hormonal imbalances, not just thyroid-related, and they all have to be corrected to restore normal metabolism.

As you are taking tablets in the afternoon is your stomach completely empty as food does interfere with the uptake, particularly if we have a fatty meal that could take up to 3 hours to digest.

That's why it's usual to take first thing on an empty stomach or at bedtime as long as you've last eaten about 3 hours previously. Some people take theirs in the middle of the night when they awake.

Yes am taking at least 3 hours from food, tried first thing in the morning and also tried the night but felt the afternoon was the best out of them all xx

It seems unusual and no wonder you are asking that question but I would email RLC labs as they would be the best people to respond. Are your tablets genuine?


Even though you are taking 3 grains - some do take larger doses, do you feel well otherwise with no clinical symptoms remaining.?

No I am constantly irritable and low mood, energy wise I have 1 good day and 2 bad....

I feel as if I have tried everything with the NDT's, as I started on armour and now on nature thyroid

I have complete brain fog worse than ever, but it's the weight issue that is seriously getting me down and making me think of converting back to levo with added t3.

I wonder (and it's only a guess) whether going on T3 only will be more beneficial for you. Maybe your body doesn't like or convert T4 sufficiently to T3 if you've already taken levo previously.

Yes been on levo for over 10 years, took me 2 years to convince my gp to prescribe NDT, so quite reluctant to go back to him and ask for levo again!

I never tried t3 with the levo, so that's why I am thinking that combo mite work?

Also never really had the weight issues as bad on levo.

Don't know really just muddled about it all at the moment, and also as each day goes on more people are saying it to me about my irritability! X

I get my nature thyroid from my local pharmacy

Maybe a change to another NDT i.e. Armour might work. It is trial and error sometimes particularly if we begin very hopeful.

When I changed from t4 only at the beginning I used armour, again no significant changes , weight was increasing and because the price practically doubled I changed to nature thyroid x

Maybe T3 added to T4 would suit you best. Weight gain whilst on a good dose of NDT doesn't sound right.

Yes that's what I was thinking x

I am on 3 grains of Naturethyroid and I experienced weight gain and further hair loss. But I can't be sure if that would have happened anyway as both symptoms started before the NDT. They haven't stopped though and I am now 11 weeks in. :(

I put on over 30 kilos during the years I was taking NDT. I went from T4 + T3, on which I was losing weight, to 1 grain of Armour, and gradually worked up to 6 grains, gaining weight all the time. I tried different brands of NDT : Thiroyd, NatureThroid, etc. Exactly the same. I became sicker and sicker, and put on more and more weight, ending up practically bed-bound. I only found a semblance of health - and lost weight - when I went on to T3 only.

That seems to be what is happening to me also, the weight seems to increase as the dose increases 😒😒

I also am experiencing hair loss.

Do u take t4 with the t3?

No, T3 only. It would appear I can't tolerate any form of T4.

Can you message me please as to where I can buy T3 reputably please 😊

Hi when you say T3 only, does that mean that you don't take any T4 at all?

OK that's interesting as I thought we needed both x

I am so glad you wrote this as it is a mirror of what is happening to me. I have always been slim and could eat anything (now you hate me!), and was on T4 for a while and ill with it, then a combo of T4 and T3 and was still having lots of symptoms. I have been on NDT, slowly upping the dose to now 3grains and although most of the symptoms have gone, I am piling on the weight. I grow most of my own food (including meat) and cook from scratch. Gluten free made no difference. I am farming, so lots of physical work, but nothing is shifting the weight. My VitD etc is OK and I am at a complete loss of what to do next. Any ideas?

Yes, this is happening to me to - been on nature thyroid for 3.5 months and gained over 12 pounds! I am regimented about my eating and hike three miles per day - no idea why the weight gain. And I am often MORE tired on the NDT than I was before I was treated at all. I’d love to hear an update from this post.

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