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Weight gain with hyperthyroidism?

Is it all that unnatural for someone with *naturally occuring* (not induced by thyroid medication or treament) hyperthyroidism to have a significant difficulty losing weight?   From the symptoms I've read about, hyperthyroidism sounds like it keep a person skinny but I'm starting to think otherwise.  

I have had hyperthyroidism since the on-set of puberty (about 14 years for me) - I distinctly remember that right around that time, I gained a lot of weight and have continued to do so.  Most doctors just assumed it was the puberty hormones and, later, stress, a question of eating too much or not exercising enough, etc., but despite really pushing my cardio sessions, I feel like I make very little difference, considering how young I am. For your info, I'm 26, never had children, don't smoke, don't drink a lot of alcohol, no drugs, and have a BMI of about 25.
15 Responses
Avatar universal
I am hyper and I have trouble losing weight. About the time I found out I had hyperthyroidism I gained a about 15-20 lbs. I have been informed that it is because it caused a faster metabolism which can make you more hungry so you eat more than you may realize. I can no longer control my weight. I eat a little and I still gain or I eat a lot and I lose a few lbs. It is very frustrating.
Avatar universal
The article "Understanding Weight Gain and Weight Loss Related to Hyperthyroidism"

by Elaine Moore says:
“On the other hand, approximately 20% of hyperthyroid patients, especially younger ones, gain weight during the active phase of hyperthyroidism. The exact reasons for this are unclear”
that means no definite answer for now, sorry

Avatar universal
Thanks for the responses.

I sweat enough as it is (keyword: *excessively*) so when I do work out, which is about 3-4 times a week at about 45 minutes each, I sweat even more yet I can't help but think that I will need to work 5 times harder to actually make a noticable difference.  
369861 tn?1306279286
I agree with you that being hyper thyroid does not means weight loss.  I gained about 50 pounds within a month's period and no one could tell me why.

I am hypo now and I still have trouble losing weight.  I have been informed that it is because it caused a faster metabolism which can make you more hungry so you eat more than you may realize. I ate less when I was hyper and more since Im hypo. I can no longer control my weight. I eat a little and I still gain or I eat a lot and I lose a few lbs. It is very frustrating.

When I was hyper, everything felt as if it was in fast mode, however, I never lost any weight.  The endo dr even said to me on one visit that I should be losing.

I tend to belive that the doctors are text book drs and forget to look at people as individuals.  What may make me fat, might make another lean?

I hope this helps.


Avatar universal
I had hyperthyroidism since early childhood and when it took a nosedive for the worse when I was 19 - 20, I gained weight (went from 105 to 145 in < 2 years), probably one reason it went undiagnosed, as the textbook definition says you should lose weight.  

However, the weight I gained didn't look like normal weight gain, it was puffy, swelling, fluid type of weight.  I guess its somewhat of a subtle difference to anyone else but me, and every doc dismissed it as just girls whining about the "freshman 15" or whatever.  It was very frustrating and upsetting as even my family made fun of my weight gain, which I knew was not just weight gain, but a symptom of a real problem that I couldn't get anyone to take seriously.

Do you know why you are hyperthyroid?  Most docs could care less what the root cause is, they just treat the symptoms.  I think if there was a better understanding of the root causes of hyperthyroidism, we wouldn't get descriptions like "the exact reasons for this are unclear" - of course they are unclear, because they are only treating the symptoms and not looking at what the underlying problem is.

I became convinced about 8 years ago that my hyperthyroidism was caused by a liver problem - here's why:  my t4 and t3 were always out of proportion - in order to get my t3 in the normal range, my t4 would have to be way above normal.  The majority of t4 - t3 conversion occurs in the liver.  While I had always had mild hyperthyroid symptoms, they became out of control when I went to college.  The dorm food was low quality - a lot of processed and previously frozen food, very few fresh vegetables and fruits, and of course I had started drinking a lot of alcohol.  When I went home for the summer, ate better and cut down on the drinking, the hyperthyroid symptoms improved.  When I realized the connection much later (at age 28, post RAI, on synthroid), I changed my diet and stopped drinking, and the t4/t3 difference improved - still not normal, but better.  I also lost some weight - maybe from the improved diet, but I lost some of the puffy, water-looking weight gain.  When I was 33, I was finally able to switch to armour thryoid (which has a natural t4/t3 balance) and within 5 months, I lost 20 pounds and most of the puffy/bloated look.  

What I learned through this is excessive amounts of t4 are toxic, and under stress, your liver fails to adequately do its filtering job, leaving all kinds of toxins and cruft in your body, which can lead to an inflammatory reaction in any cell of your body.  You can gain weight just due to the inflammatory reaction which will cause fluid retention.

I'm no doctor, but imo this makes a lot more scientific sense then the cop-out doc response of "oh you just eat too much" - so its all your fault.  Considering all those diet pills out there are looking to speed up your metabolism and endothermic reactions and the increased t4 will do that for you, eating somewhat more is unlikely to cause a significant weight gain unless you are eating enough to keep an IHOP busy 24/7.

This is my own experience and may be very different than yours.  There's nothing you can do outside of your doctors help to reduce your t4 level, but you may be able to help your liver cope with the stress by getting some direct sun exposure (breaks down certain toxins like bilirubin that would otherwise have to be processed by your liver - for babies with jaundice they use uv lights to break down bilirubin and suggest you put your baby in a sunny spot for a little while each day - same principle), and for diet, cut out processed food, red meat, shell fish, and sugary foods/drinks, and eat plain yogurt, fresh vegetables and fruit, and lean protein.  And don't drink alcohol.

I hope this helps or at least gives you some ideas of what you could do - i know from experience its boiling-point frustrating to be told there's nothing you can do.  
Avatar universal
I gained 14 kgs in 2 months and it sure wasnt from overeating as I kept a great natural diet.I went from a size 10 - size 14..yukk and I get on an electrical treadmill twice a day for 20 minutes each time. I have lost 1 kilo after doing this for 3 months but my levels in the thyroid have been eratic, I have been overdosed and ATDS and my liver enzymes are STILL raised.
I put mine down to being severely hyperthyroid and high doses of anti-thyroid drugs which in turn caused raised liver enzymes (as kkb23 has just stated).
What kkb23 has posted, I agree with 100%.
Hyper and gaining weight??? Pffttttt
Thats what friends tell me lol.
Then I say....LOOK AT ME!
They then try and tell me I am HypO and not HypeR.
Yeah right lol
With FT3 and FT4 up sky high and hardly any TSH and I'm HypO???

No I totally agree with kkb23.

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