I am interested to know of others experiences with weight loss and/or gain.
It is confirmed I have underactive thyroid hashimotos. What puzzles me is that since I have been taking Levothyroxine (50) I have lost a lot of weight which I was not expecting. I always thought underactive thyroid would result in me gaining weight instead. I was carrying extra weight before diagnosis so I am pleased with the weight loss as I was concerned when first diagnosed that I would put on more weight but this hasn't proved the case. In fact it is a concern to my endo and GP who are currently looking into the root cause. Whilst I am pleased with the weight loss, I am more concerned that it is not a healthy way of losing weight and want to understand why?
Does anyone have a similar experience? Any ideas what may be the reason for weight loss as I am forever learning about the very complex hormone system we have.
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It's often the case that weight gain is a symptom of hypothyroidism. When diagnosed and on Levothyroxine, if optimally medicated then weight loss should be possible and often is. Many people lose their "pre-diagnosis" weight gain, I certainly did, I think I lost about 2 stone over time.
How long have you been on Levo?
What are your current test results for TSH, FT4, FT3, thyroid antibodies?
Is your weight loss severe and sudden or has it been gradual?
Do you have Hashimoto's (raised thyroid antibodies can show this)?
With Hashimoto's coeliac or gluten intolerance are very common
Becoming more gluten intolerant on Levothyroxine is very common
Obviously coeliac disease is often linked to weightloss
Being under medicated can, for some also cause weightloss
Gut function can be significantly affected when hypothyroid
50mcg Levothyroxine is only a starter dose
Do you have recent blood test results and ranges to add
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
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).
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)
Changing to a strictly gluten free diet may help reduce symptoms, help gut heal and slowly lower TPO antibodies
While still eating high gluten diet ask GP for coeliac blood test first or buy test online for under £20, just to rule it out first
Assuming test is negative you can immediately go on strictly gluten free diet
(If test is positive you will need to remain on high gluten diet until endoscopy, maximum 6 weeks wait officially)
Trying gluten free diet for 3-6 months. If no noticeable improvement then reintroduce gluten and see if symptoms get worse
How much weight have you lost? And over how long a time? Hypos tend to retain water, which is quickly lost if you get on the right dose - and if you're lucky! Fat takes longer to lose. So, perhaps you just had water retention.
Many thanks to you all for responding. Weight loss has happened since taking Levo starting in May this year probably averaging 4lbs a week but not as consistent as that. Some weeks nothing then other weeks alot. There is no question that I was overweight and struggled with my weight all my life however previously I would always have to do lots of exercise and running/dieting to lose weight but since being diagnosed this has not been the case. In fact for the majority of my time since May, I haven't been able to do any exercise due to severe joint/bone pains and feeling very unwell. I still have this to a certain extent but am a little more mobile and feel a little better. Unable to do most exercise though hence my concern with my weight loss as this is not the norm for me.
I have seen a very good endocrinologist recently who is concerned with the weight loss too and currently having various further tests.
The aim of Levothyroxine is to increase the dose slowly in 25mcg steps upwards until TSH is under 2 (many need TSH significantly under one) and most important is that FT4 in top third of range and FT3 at least half way in range
Your FT4 is only 45% through range
FT3 only 25% through range
Helpful calculator for working out % through range
Most people gain weight when hypothyroid, but a significant minority struggle to maintain weight until adequately treated. Either because they have no appetite or because the gut is badly affected and not absorbing nutrients
NHS guidelines on Levothyroxine including that most patients eventually need somewhere between 100mcg and 200mcg Levothyroxine.
I lost about 1.5 stones after being diagnosed with Hashimoto’s and put on Levothyroxine. I find it incredibly difficult to loose any weight having Hashimoto’s even though I exercise and eat well. If I so much as look at a chocolate biscuit I put on weight 😆
I’ve lost weight since having Hashi diagnosis and increasing Levo. However, I think in part it’s due to me being Gluten Free for 10months now- I’m certainties more careful about what I’m snacking on as gluten seems to be everywhere. I also recently tried 3 months of dairy free which did cause more weight loss. I’m slowly reintroducing dairy as wasn’t convinced it was adversely affecting me. Have you cut anything out of your diet Health41?
I put on a lot of weight before diagnosis. I started Levo in Feb at 25mcg’s only and lost 8kgs over next few weeks but then the weight loss stopped even though I’ve been titrated up to 125mcg. I probably still am a further 8kgs overweight.
Thanks for responses. Whilst I wouldn't say I have a 100% gluten free diet I do hardly eat gluten and have steered clear of it for those reasons. I haven't changed my diet much since being diagnosed but I am someone who eats lots of health and fresh food.
I have been on Levo since May and am just about to go up in dosage based on the endo's feedback. He has been very thorough along with my GP too. He has highlighted things to be checked which may be impacting on symptoms I have.
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