Suddenely losing weight: I have been battling... - Thyroid UK

Thyroid UK
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Suddenely losing weight

I have been battling with my weight for 6 years or more and even thought Im on T3 Im still not losing.

Is it possible that once you get to optimal levels (I think I may be there now) that you can start to lose weight and if this has happened, how easy is it.

At the beginning of this year, after Christmas and New Year I put myself on a high carb/low carb diet. I haven't been perfect but Im doing okay.

At last I seem to be losing weight. I can only assume this is the right diet for me although Ihaven't starved myself and have been out for meals etc so not exactly religious with it.

The weight seems to be losing easily though and of course, me being me, Im starting to worry about why Im losing weight.....typyical but I guess I just need to know whether anyone else has experienced optimal levels and the beginnings of losing weight. How hard did you have to try?

14 Replies

I think you've hit the sweet spot! :)

I started losing weight as soon as I gave up gluten - which meant a generally lower carb intake. I have lost 5.5 kilos since July last year and am still going down slowly, and even better, I'm not even trying to lose weight or feeling hungrier. All this started before I was put on Levo (beginning of 0ctober) and I'm currently taking 25/50 mcg Levo alternate days, so hardly a high amount. Ideally I'd like to lose another 5 kilos to return to my pre-back injury weight.

Sounds like you're on the right track! :)


I have been struggling with weight like you for so many years increasing by a stone every year despite a fairly good diet. I have recently started a keto diet which is similar to a low carb/high fat like yours and I am losing pounds almost daily. I am down 11lbs in 2 weeks. I am also gradually increasing my NDT to see if it helps raise my chronically low body temperature and in the last two days I have seen a significant change. I started this new plan as part of a programme to heal my MS and I am amazed with the results so far. Keep in with the diet as it will help you in more ways than you can imagine.


Don't worry too much about losing weight it means you are in the correct place. I began to lose weight quite fast for a while, then after a few weeks it slowed down and now it's a nice steady pace and has been for about 12 months. Previous to this I couldn't lose anything ever so it had everything to do with my thyroid levels. Low carbs will also help every time. I am a total carb monster and often fall off the band wagon but when I stick to low carbs, high proteins and good fats it comes away quicker. I am currently on a low carbs diet due to gestational diabetes which isn't such a big thing for me and still losing at a healthy rate despite my baby bump getting bigger. I've hardly gained any excess weight during this pregnancy at all which is a first for me. Well done x


Sounds like you are doing really well. I first put on all my weight in my first pregnancy almost 30 years ago! 6 stone and I have been stuck with it ever since. I hope all goes well with you and the baby. Best wishes. X

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Thanks Sally I put on loads with my first also. Think it was about 4 and half stone but lost it pretty quick, within a year of having her. Then my 2nd I lost weight but piled on loads after. That's when the nice hypothyroidism kicked in. My third I couldn't even keep water down the entire way through and ballooned big time after him but was skinny as a rake within hours of having him. This was all before being medicated. I put on some obviously where you are meant to but looking back now I was swollen more than anything even in my pregnancies. Was like a roller coaster of rapid weight loss and weight gain. After my third I just couldn't lose anything at all. It's tough losing any I know, thyroid problems do the most bizarre things to our bodies. I'd much rather be able to eat and lose slowly though which I can this time and sounds as if that is what is happening for you X

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Is that low carb high fat? (You've written high carb/low carb :) ). If so, it's the only diet I ever lose weight on. Everyone raves about SW but I actually gain weight when I do it!

Do you feel well? It's much less likely to be something other than the diet if you're feeling ok.


I'm going to go out on a limb here and tell you my opinion, can I underline opinion here? Hehe I don't want any members getting upset with me.

I believe that it's your diet that is helping. I don't necessarily think that for most people T3 is "necessary" to lose weight, but this is mostly from my own experience, I'm sure for some people it's essential.

My experience: I've been under medicated for a year now, haven't had a good TSH reading, low t4 and low t3. I just got put on a higher dose of t4/t3 two days ago and I'm finally starting to feel right. However, even while being under medicated I was able to lose 50lbs in the last year by diet alone. AIP diet to be exact, I avoid all junk food, no preservatives, no canned foods, no crap. I make everything fresh and cook every meal. While they've raised my T3 I didn't notice any extra weight loss, if anything it's finally plateau'ed and I feel I'm at a good weight.

All doctors / naturopaths, and family members all agree it's the diet. I've even tested it by cheating on my diet a couple days (as an experiment), lo and behold I gained 2 lbs during those days.

Don't be worried about the weight loss, I started losing it FAST when carbs were taken out, but I had a lot of extra weight to lose! Just make sure you check up with your doctors, check your vitamin levels and get your labs done, eat nutrient rich foods, and as long as everything is in order, this is just your body finally kicking and adapting to a healthier environment.

Keep up the good work!



See I was the opposite. I couldn't lose a Ib in weight whilst doing diets when not medicated. I suppose everyone's body has that point where your metabolism kicks in again but for me it wasn't until my t3 was top of the range. I walked 8 miles a day and put on weight on diets previously including weight watchers, diet chef and the Atkins diet.

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Absolutely, everyone is different. We all have different roads to success. Glad to hear the t3 worked for you!

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Hi what is your typical daily intake of food please. I have just started on a low carb diet myself after watching a video on here about gluten and thyroid.

I think I'm losing weight but it's only been five days. I will weigh myself on Monday but it would be interesting to here what you eat so I can get this right.

Your sudden weight loss is because of the low carbohydrates.


Ive sort of answered this below, only just now. So you wouldn't have seen it. Its a cross between high carb and low carb actually and its 5 meals a day with only about 250 calories in each. I find it very easy because I can deal with the small portions especially as its very tasty and because I know that in a couple of hours I will eat again.

I hope that helps

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Hi, hope I'm not hijacking this reply, just wanted to say when I went gluten free and low carb it took a while before I saw results, it was slow at first, but after about 3-4 months the weight really started shedding (it helped when I switched to full AIP diet). Could just be my personal experience. Best of luck!


Im going to cover all points here and tell you why I don't think its jut the diet. When I say High carb/low carb I mean 4 days high carb/2 days low carb and one day an extra 1k calories. I have been on 600 calorie a day diets and still never lost and I definitely didn't lose weight with SW or WW. I lost only 1 and a half pounds in 18 months with those.

My Daughter has type 1 diabetes, we have also ate very healthily but even more so now. Only very low sugar diets, we don't eat junk food, I don't drink much, we have no treats drawer if you know what I mean. So to actually start losing weight now is unusual.

I have been gluten free ish for a couple of years now because it helps my joint pains. I should add that I was involved in a bad car crash about 20 years ago and Ive never been right since. I have alot of pain (even wondering about MS as time is going on and as I have other symptoms) and the weight gain started after that.

So, as I said, I worry about any weight loss because its so unusual for me but I guess I have to keep an eye on it and hope its just the sweet spot thats working.



Well done Numberone, got to say I'm a little jealous :-)

I'd say not to worry unless it's sudden drastic weight loss. It sounds as though you're medicated properly & your metabolism is doing its job, it sounds like a great place to be.

I've tried allsorts to lose weight & nothings happening - I may try the carb cycling & see what happens.


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