Losing Weight? Anyone doing the 5:2 Diet? - Thyroid UK

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Losing Weight? Anyone doing the 5:2 Diet?

I am getting increasingly frustrated with attempts to lose the weight I gained since first thyroid attack. Has anyone tried to lose weight using 5:2 diet? Did it work? Did it take longer to get results than for people who are not hypothyroid?

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you may find you struggle with losing weight until your thyroid is optimally treated. I haven't tried the 5:2 diet because it is simply too difficult for me to fit in my active lifestyle. I work in an infant school 5 days a week and there is no way I could survive on 500 calories on any of those days; and on a Sunday (also a thursday and sometimes a friday) I do karate which I definitely can't do on so few calories. I have thought about doing it 6:1 instead as I have looked into the science behind intermittent fasting and it looks sound. I have a friend who is doing 5:2 along with healthy eating and she is doing very well with it, but she doesn't have a thyroid problem.

I think it is worth a try but if you are not optimally treated you might find it takes longer than for other people.

Let us know how you get on with it :)

Carolyn x

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i hv read something about iodine plus 2 tablets which u can buy from u.s.a.online.if anybody knows anything about this pls let me knw ,or if anybody has tried them.



Iodine is a very controversial subject:


I would very much hesitate to suggest it as a solution for weight loss.


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I am still struggling to lose weight. I am fully medicated and have lost some weight it is just that I regained some of it because life (and parties) got in the way, and oh yes and then Christmas!

I always think that if there was a magic answer then Oprah Winfrey and other overweight celebrities would have found them by now as they could afford to try them!

I have always read that we should steer clear of iodine and have never heard about 5:2 ?? This is my take on losing weight:-

1. Make sure that you are fully medicated - that your TSH is under 1 and your Free T4 is at the top of the lab range and your Free T3 is around 3/4 of the lab range.

2. Eat lots of vegetables, salad and fruit, chicken and fish, eat regular meals and only drink a couple of glasses of alcohol per week

3. Move as much as you can and as often as you can.

We all know that it isn't rocket science, burning more calories than we consume is the answer.

A friend (who I have met at Slimming World) has lost 7.5 stone in 15months and is hypothyroid and has type 2 diabetes and also a lady in Wales I know has lost 15 stone in the past 2 years and is hypothyroid and they have had good weight losses each week.

Hope that helps.

Good luck.



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Sue, I agree with most of what you say, there, but I would totally disagree with what you said about burning more calories than we consume being the answer. If only it were that simple! If it were, I doubt if any of us would be overweight. It certainly isn't that simple when you're hypo. We hear so often on this very forum about people running miles and miles and going to the gym etc and still putting on weight. Are you suggesting that these people are pigging themselves out on a daily basis? If they are keen enough to go to all that effort to lose weight, would they really stuff themselves when they got home? I doubt it.

Did these people you know that were hypo and lost lots of weight have Hashi's? Because with Hashi's you can lose a ton of weight - and then put it all back on again, and more. Maybe not immediately, but in time. Been there, done that, got the baggy skin!

One very important thing to remember is that when you are hypo, you can diet yourself fat. It is very important to eat enough calories - and that might be more than you think.

Exercising is not just a case of going to the gym and riding machines, lifting weights, etc. 'Exercise' is every move you make, and every bodily process, and it all needs calories. And if you don't have enough calories to convert your T4 to T3, T3 to T2, etc, you're going to get more and more hypo, and thus fatter and fatter. As I said, been there, done that...

Hypos usually have low appetites anyway - not always, of course, but... And they have difficulties with digestion, and absorbtion... And the probability is that they don't get enough calories to fuel their bodies. So they didn't get fat by over-eating, so why would one expect them to get thin by under-eating? It isn't logical. So asking them to then cut down on their food intake - as so many doctors do! - is just pure cruelty in my book. So if this 5:2 diet (which I have never heard of) is only 500 calories a day, as seems to be suggested, it just isn't enough.

And then suggesting they should go to the gym, with their aching muscles and creaking joints, low stamina and long recovery time... it's inhumaine! And did you know that if you don't enjoy the exercise you're getting, it isn't going to do you any good anyway? (I have that on good authority.) And who is likely to enjoy it under those circumstances!

So, for us hypos, the most important thing is getting our hormone levels up - and, to be honest, we're not just talking thyroid hormone here, there are other hormones that need to be optimal for us to lose weight, such as testosterone (yes, even for the ladies) and HGH. Hopefully, if our thyroid hormones are optimised, the rest will fall into place, but it's something to bear in mind.

I seem to have gone on a bit, here, but it's a subject dear to my heart having been hypo all my life and had weight problems all my life!

Best wishes to you all, Grey


I really appreciate you having "gone on a bit", Grey! This is really interesting and makes all the sense in the world to me. I have long realised that the usual calories & weight gain are not related, in my body anyway. (I remember doing the Milk Diet at school, very popular in early 60's. I put on 7 lbs!!!) When I staggered into my doctor's, clearly hugely overweight, exhausted, round face, coarse hair, aching joints, weak muscles, depressed - they said "Oh we must get you back in the gym" It would have been nice to have been able to get up the stairs! Well that is in the past, so moving on. Hmm. Well, the 5:2 diet is not just about weight loss; it's also about giving the body a rest and improving bloods, optimising chances to avoid cancer, diabetes etc. (Both those are in my family) Dr.Michael Mosley did a report on 5:2 in a Horizon programme (you could look on YouTube), and there's plenty of science around it. The 500-600 calorie intake is not continous! There are just two "Fast Days" (ie limited calorie intake - you still eat), so two days out of the week - hence 5:2. It may be that 6:1 is better for me (thinking of your advice). In effect, you eat 25% of your normal calorie intake on two days out of the week. Re testosterone: how interesting! Well, I am taking Maca which I understand supports both testosterone production and the thyroid. Anyone heard anything about Maca??


Hi Liza,

I have been following the 5:2 diet since August it works very well and is easy to follow, as you can move the fast days to suit. I save my food till evening , I have no problems with feeling low, or shakes, starving yes but you know you can eat the next day, I often feel the best on the fast days.My weight loss is slow and steady 1 to 11/2 lb a week for me is now a way of life have spent the last 40 yrs trying every other diet !

My sister takes Maca and has reduced her thyroxine by 50 mcg it give me headaches, though this was before I was diagnosed as hypo.

Give it a try. the diet .

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Grey, Just to clarify - NO I am not suggesting that anyone is pigging out!

I am not accusing or suggesting anything about anybody.

I gained 4.5 stones whilst battling to be diagnosed and properly treated with hashi's. I know what it is like to gain weight whilst following a diet.

I am not talking about when we are fully medicated which I believe that I am.

When I follow the Slimming World diet then I am able to lose the same amount of weight each week that I could years ago prior to being hypo.

Maybe this is because I have a higher testosterone level?

We are all different no two people's metabolism is going to be the same.

I am just being honest with myself that the weight I have gained over Christmas has nothing to do with my thyroid disease it is because I mainly sat down all day, drank alcohol most days and over ate.



lol Merry Christmas! Hope you enjoyed it, Suze.

Yes, of course everyone is different and all we can do is generalise. Put information out there and see if it fits. But I really do feel that too much 'blame' is put on the patient these days - perhaps it always has been? I don't know. I just know that we aren't responsible for our symptoms, and one of those symptoms is putting on weight more easily than others.

Yeah, ok, so sometimes we do over-do it on special occassions. Why not? We're entitled to enjoy life like anyone else. But there are lots of people that that wouldn't hurt. And the question is why. Why can some people eat what they want, and as much as they want, and not put on weight? And why do others struggle? And the answer, I'm 99.9% sure is because of our hormonal make-up.(If you have a higher level of testosterone, good for you! Or was that sarcasm... But obviously we don't want too much!)

Yes, we should all be honest with ourselves. But there are many, many hypo sufferers that are being honest with themselves when they say that they don't eat much, eat 'healthily' and get a lot of exercise, but they CAN'T lose weight - and some of them even continue putting it on despite their doctors telling them they are 'adequately' medicated. And for them, calories in vs calories out is just meaningless. (Although we have been brain-washed into believing it like a mantra.) And making them feel guilty isn't the answer (no, I know you didn't intend to make them feel guilty but I'm just generalising). Feelings of guilt do not make for good health, so please, everyone, let's stop blaming the patient! (Plea to doctors here...)

Grey x


Hi Lisa

There is someone doing the 5:2, but I can't remember who! I've added the 5:2 bit to your question so that it might 'draw them out'...! ;-)



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Hi My endo always says the diabetic diet ( see WEB ) is best. Are your results good? It would be a good idea to post them. Also are you taking T3? it often lowers the TSH but it is normally, people find related to over weight . If your body is not converting T4 ( levo) to T3 as it should it would show in a Free T3 test, make sure you have one done not just T4 and TSH,

Best wishes ,



Hi Jackie, thanks for your reply. Yes, I am taking T3. At first that's when the weight started to come off me, and I got some of my waist and shape back. I dropped from size 22 to 18 in about 9 months. T3 has helped me regain my muscle energy and took away the mind-fog within less than a week. Been taking Cytomel since April 2010. Going to specialist next week for a check-up. I guess I could ask the doctor for a Free T3 test but they are so suspicious because I'm seeing a non-NHS specialist and taking non-BPS meds. And because they spent 9 months reaching a conclusion that there was nothing wrong with me because my T4 was fine. I find my doctors very unknowledgeable about Thyroid. My frequent visits about real physical symptoms were interpreted as hypochondria. They prescribed me Prozac which I refused to take (it undermines the thyroid!). My specialist however understood the problem straight away, but then he has had so much more training around Thyroid that GPs.


Hi Yes difficult unless under a private endo as opposed to a private doctor.Have you asked the private doctor to test the Free T3, that T4 and TSH plus Vit D should have automatically been tested before the start of treatment. Have you thought of having tests using TUK site bloods thyroid.uk.org( boods) if you use Blue Horizon they are really the Lab called the doctors Lab ( TDL ) which is what all the private hospitals use at a fraction of the cost. So, important as then well known to docs. i have the intermediate test with quote TUK 10 it costs about £ 6o no authorisation and al done on the PC, results in a few days. Do not take thyroid drugs before test ( am ) and only do it Mon to Thurs because of the rotten postal service. i use them very, very often. very good and efficient.



Hi Everyone.

I did try the 5-2 but only got to day 4 as I count manage the low feeding days. It did sound good at the time.

I have hashi thyroid (totqally dead) and am on 125 levo. I am only about 20lb overweight but we all know its not funny when we have a bloat day.

I have done most diets printed but recently I am trying to reprogram myself NOT TO DIET.

The most inportant thing is to get the well feeling, good numbers from blood tests and the finding and accepting that we aren't perfect. I might be 13 stone and size 14-16 (5ft7), but I'm real, and never going to be skinny minnie.

When we are well in ourselves we can overcome the aches or pains from exercise and focus more on the good things to eat.

I do agree with Sue that you have to eat well and move more. By doing this I am losing inches.(2 weight workouts and two 40 minutes walk each week)

I have found that by writing down what is being eaten I was kidding myself, i was eating more than I believed. how many biscuits can one woman forget she had?

I would suggest to undiet for a little while get the well feeling. a frustrated head with 20 DIETS going round it won't work

Good luck and takecare



I don't know much about this diet but the down days sound hard. I only lost weight(despite previously eating very healthily and exercising a lot before I got really ill) on the Dukan diet. It's a tough first week but ay least you can eat when you're hungry and then you gradually start to add things back in. I'm not on it any longer, just back to my healthy eating but still having treats when I want and haven't put the weight back on.

When I visited Dr P and told him this was the only way I'd managed to lose weight in years, he said he though it was a pretty good diet too.

Good luck with your weight loss whatever you decide :)


The down or Fast Days are not that bad actually. Mind you I've only done 2 so far! I have 2 small meals (brunch and supper). The thought that I can eat what I want the following day is a motivator. I feel like I am unburdening my body. The flexibility is good too, no prescribed foods or set days.

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I wouldn't dare try with my symptoms and belief that I'm not properly treated yet. I don't like the idea of depriving our bodies of nutrition. Even temporarily... but good luck because there's always that feel-good which helps if you do lose weight.



Like you, I didn't deprive myself in those early years of hypothyroidism, partly because Nothing Worked weight-wise. You must trust yourself. We are all different and at different stages of recovery, balance, optimisation. And I am going to discuss 5:2 with Dr P next week. And you are right about feel-good factor; from the blog posts of 5:2-ers there's lots of mood & psychological benefits which go far beyond the rather infantile "I've been good today". The only drawback seems to be calorie-counting which I've always said is a criminal waste of a woman's brain!


It's good you are also communicating with Dr P... and yes ... calorie counting..lol!


I did the 5:2 way of eating for five weeks before Christmas and am about to start again (just too difficult at Christmas). I was pleasantly surprised at how easy it was, but I (honestly!) don't eat much usually and eat fairly healthily with occasional treats. I found that having five (100 cal) snacks through the day was the easiest way on 'fast' days as I think this helps to keep my metabolism up as it doesn't take much for it to plummet - which, it seems to me, is what happens whenever I cut calories. I also took an eighth of an armour grain extra on 'fast' days to help this problem, though I wouldn't recommend this generally without proper advice but It seemed to help me and the fasting diet was really successful for me as I lost a steady 1lb a week for four weeks. So looking forward to losing what I put on over Christmas and, fingers crossed, some more as well!


I did try a slightly different take on this which was to not eat after 3 p.m. on two days each week. I managed it when hubby was away and lost 1lb on each day but when hubby came back and we ate as usual I put it back on. I might have to lay down the cooking utensils and do the 5:2 but tricky when cooking proper meals for other half.

Which reminds me...relative gave me a cutting from Reader's Digest from a nutritional doctor who said that...wait for it...getting fat had nothing to do with the thyroid gland, it was over-eating which made people fat. In his professional life he had seldom found his over-weight clients to have hypothyroidism. My relative is always telling me this and I have to restrain myself from hitting him.

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Well it is now over 2 months since I started 5:2 Way of Eating (not calling it a Diet!). I have done 2 Fast Days every week during which I've eaten approx 500-550 cals. I have lost nearly 2" from my waist (7" to go, then. Sigh!) 3 people have told me that I've lost weight which is encouraging. I haven't magically dropped a dress size like many 5:2 enthusiasts but my upper torso and face are thinner. Slightly. The progress is snail's pace - probably 2lbs a month - but in the right direction. Finally. A bonus point is that my digestive probs have 90% disappeared. Slow progress is frustrating but better than none. I shall keep on with this & report back. If I maintain 1-2 lbs weight loss a month, I will be back to my pre-Hashi attack weight by the end of the year. And it really isn't that hard. Just slow for me.

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