Weight Gain on Tamoxifen

Hi can anyone help. I have been on Tamoxifen for over a year now and have put on over a stone in weight and it seems to keep climbing!

I have recently been back to see my consultant and she told me to go on a GI Diet which i have,but instead of losing weight i have gained more.

I find that being on Tamoxifen i feel as if i am hungry all the time and once eaten i could quite easily fall asleep. Tireness also seems to be an issue and i have no get up and go anymore.

Does anyone have the same problem, would be very grateful for any advice or help as it is starting to get me down. Thank you

Hi lol1968. I haven’t got any answers but I have the exact same problems as you. I’m finding it incredibly hard to lose weight, and pre-BC I never had to bother with weight as my appetite and energy levels were fine, but now food / eating / weight has become an issue for me. I want the old me back.

sorry Lol - another one here without any answers but lots of empathy. I’m exactly like scottiedog - i’ve been so fortunate all my life not to have to worry about weight and now its an issue. I’d say i’ve gained approx 12lbs in the year since DX and cannot shift it.

So sorry i haven’t got any answers - hoping some ladies come along who do.


Now I know what’s wrong with me!!! I find most days, I need to sleep for a couple of hours in the afternoon. I also seem to be hungry all the time and, yes, I have some weight gain. Never had to worry about my weight before.

I’ve been on Tamoxifen for a year.


Hi lol

I am posting a link to the publications page where you can look at a couple of BCC publications which may be of interest to you about diet and breast cancer and eating well:


Take care

I am so glad it isn’t just me. I am doing regular exercise and trying to eat healthily but have put on 1 1/2 stone since finishing chemo a year ago. My GP just tells me to stop eating biscuits, so I have given them up for Lent, and have put on a few pounds since!!!

I dread to think what I will have put on by the time I have been on tamoxifen for 5 years.

I’m glad it’s not just me…I have gone from a size 10 to size 14 and still growing. Problem being I can’t stop eating then sleeping.

Then the other day my OH really shocked me, he said “I have supported you througout your cancer, but cannot stand me being chubby”

That hurt alot, but I just don’t know how to loose the weight,i’m craving for food constantly! He has been very supportive through all of this but he just hates weight on women, it’s like he has a phobia almost. I can see this could split us after 21 years together…

Any advice would be greatly appreciated.

love Teresa xxx

Another one here struggling with the weight gain. I have always had to watch my weight but I don’t seem to be eating any more than I used to and yet the weight is piling on. I’ve probably put on about 10/12 lbs since finishing chemo last July. It really came home to me yesterday when I went shopping for summer clothes and felt so frumpy in most of them.

Beverley xx

I kept putting on weight on tamoxifen and no matter what I tried it didn’t seem to work. One doc at the hospital actually told me i would never lose weight while on it. I switched to femara (noticing with great interest that it can cause annorexia - no offence meant regarding a serious condition.) Some months later I have started to lose weight and have lost 1 stone 7 lbs so far fairly easily, without ever being hungry and also eating out (with puddings) every week. Not sure I deserve to lose the weight, my main changes were switching to chilli rice cakes and pink and white marshmallow biscuits for lunch instead of just fruit? I eat dinner and breakfast as usual but I also changed to sugar free squash. Everyone I know has gone out and bought pink and whites in case they hold the magic cure lol!I’m sure its the tablets, probably something to do with tamoxifen also being a fertility drug.
Good luck and it will happen.

Oh Muffett (Teresa), I’m sorry your OH isn’t coping with your weight gain, that’s the last thing you need after everything else. I know mine is also struggling a bit with this, but for us it’s because I feel so flabby and unattractive and he sees that my feelings about myself have changed for the worse. If he criticised me openly about my physical weight I’d be truly devastated and very p***ed off with him. However there is a perception in society (held by men as well as women I think) that eating is purely a self-control issue for women, and therefore that the thinnest among us must the most in control of their lives and as a consequence the most attractive. I disagree (and thankfully so does my OH) but we girls are all subject to these kind of pressures and peceptions whether we agree with them or not. Part of my negative view of my weight gain probably stems from how I think other people see me. Good luck in dealing with this with your partner. A year or so ago there was a weight loss thread started - I didn’t last long on it as I couldn’t shift the pounds, but maybe some posters had some good ideas. I will dig around for it. Interested to read from Lily that changing from Tamoxifen to another tablet worked. not sure I’m brave enough to change my tablets. I’m NED at the mo, and “if it ain’t broke don’t fix it” comes to mind. I will watch this thread with interest. Take care all you fabulous ladies.
scottiedog xxxx

Another one struggling here! I lost 3 stone during treatment but since since then I’ve gained 2 stone. My Onc told me it was the tamoxifen. I’ve never eaten so healthily, in fact my cholesterol levels have dropped right down. I exercise every single day too.
I find I’m getting more fat around the middle and above the waist which I never had before.

I’ve been very tired since treatment and that could be in part the tamoxifen. I wonder if its slowing us down a bit and therefore slowing down our metabolisms as we’re less active than before? I certainly feel slower.

Elinda x

hi all, new to bcc forums. i’ve been on tamoxifen for just under a year now and have put on about 2 stone since all my treatment begun. i always had a flat stomach even after having 2 children, but now it’s constantly bloated and uncomfortable. i’m 37 years old and feel i have lost my libido i just want to go to sleep. sometimes i feel so drained and low.

Thank you to all that have replied, its nice to know that there are so many of you in the same boat struggling with weight gain.

Teresa - really sorry to hear about OH and his problem with your weight gain. I hope it all works out well and that he can overcome his fears.

Lily200 - Did the onc decided that you should change to Femara or was it your decision?

Thank you again ladies and good luck to you all. Any advice much appreciated.

Lai xx

Morning ladies. I spent alot of time and money trying to lose weight last year, put on through another medicine for a different illness, I needed to loose 4 stone, with hard work and determination I lost 2 before my bc diagnosis. In the 2 months prior to starting chemo while taking tamoxifen put on a stone, all the clothes I had given away had to replace. Really knocked me. I found and still find it’s the exhaustion I find the hardest as I can’t exercise anymore. And since chemo the other one had gone on, so back to what I was with the fear of where I will end up. When I was first diagnosed I came up with a flippant comment of a least I might get down to my size 12 easy, to which they smiled. Now I know why.
If anyone finds a way to shift the weight I would be so grateful x

Hi, thanks for your comments, I think what also pi…s me off is when I was first DX he was waking me at 6.30am with breakfast almost force feeding me! Chocolate, steaks cooked in rich sauces everything I wanted as he said weight you need when your ill!

It was okay then for me too put on the weight and to be honest again he was right as I did go very thin whist on chemo… So i suppose without the original weight gain I would have probably been quite ill.

I have now been making veg soup with no creams etc, so trying to eat this in snacking rather than cheese and crackers, crisps, etc, all that I crave for!

The other thing is because of the SE being so horrendous for me on TAM my Oncologist wants to put me on anti depressants, but surely these will too bring other SE… Not for being depressed but for the hot flushes!

Love Teresa x

Hi elly09

Welcome to the forums, you’ve come to the right place for support as the users of this site have a wealth of knowledge between them.

You may also find it useful to contact our free helpline on 0808 800 6000, opening hours are Monday to Friday 9.00 – 5.00 and Saturday 9.00 – 2.00.

Best wishes
June, moderator

Hello everyone - I have been on Tamoxifen since April 10 and was worried about putting on more weight. Had put on about a stone and already need to lose weight before dx. and my knees and feet were very painful so knew I had to do something about it.
Went to Weight Watchers in Aug on the spur of the moment (not something I had ever fancied doing before) and have now lost over
1 1/2stone, although am now finding the loss is slowing down.
The main thing that helps me is writing down EVERYTHING I eat - has stopped me eating biscuits and cakes with every cup of tea!! Got into really bad habits during chemo(was the Carbs Queen) and this is helping a lot.
Try to do at least 2-3 walks of about 20 mins a week but like everyone else find I am very tired. Wear a pedometer everyday to encourage me to walk more. So I am hoping that I can control my weight while I am on Tam and at the very least not put any more on.
Good luck everyone. Marli

Hi elly09 just want to welcome you to the forums.

I feel exactly the same, the weight gain is getting me down considerable especially now with the warm weather we are having. I too, once had a flat tummy like you even after having my 2 kids too. Now the weight is all round my middle and higher. I get very bloated and i don’t know about you all but flatulence has also been a problem too!

I get very tired round about 4:30ish and if it wasn’t for having to get tea ready i be fast asleep on the settee. I also find about 7-8pm a bad period too as get very weary then, but i definitely have lost all the energy that i once had once treatment began. Also getting up in the mornings is a problem as i find i just want to sleep. Anyone experience the same?

Let’s hope it gets easier the longer we take it!!!

Lol 1968
the aromatase inhibitors, femara is one of them, have been found to have a bit better stats than tamoxifen but only once you are post menopause. I was around that age and nagged until he gave in and let me switch, this took some time I have to say. There is a lot of debate about this with some oncs preferring people to stay on tam, some needing to because they are too young to switch or medical reasons. Some say it is used as it is really cheap but it is actually one of the most successful drugs ever. Views differ a lot on this and hopefully the decision is not a financial one for any of us. It is complex though.I had terrible ankle stiffness and pain on it too, making exercise impossible.
I was told that you can have silent periods on tam, being a fertility drug and to take great care!
I had 2 years on tam before switching.

I am an old lag - i was here three years ago after diagnosis of invasise lobular cance,then Mx, chemo and rads. The hormone test they did gave me a hormone age of 35 which quite chuffed me because i was nearly 50 by then…i had been fine till tam and that plunged me into sleeplessness and sweating any time of day and night - i was an impressive dripping tomatoe. I tried several drugs to get it under control and megace seemed to help but i decided recently - maybe rashly, but with onc agreement to stop taking it because i am nearly 53 and menopause should be pretty much done. i am no better no worse - i sweat more now because oh yes i gained weight, so everything is more of an effort.

My almost slim nearly 85 yo old says oh you’ve got fat… (thanks Mum). My sis who had same cancer as me the year before puts a lot of effort into exercise… errrmmm she’s not as thin as she was either!

best of luck me dears - this hormone treatment does make us fat according to my onc. but we live and enjoy - much love to all j x