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Fasting with Medical Conditions

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4:3 for Hypothyroid?
27 Jan 2015, 22:07
Hi, has anyone successfully or unsuccessfully tried 4:3 at 1000cals on fast days. I am Hypothyroid and interested in what would work best for me. The 1000 cals 4:3 thing was suggested in this site for Hypothyroidism and I wondered if anyone did it? Surely this is not technically a 'fast' so cant have the same benefits? :confused:
Re: 4:3 for Hypothyroid?
27 Jan 2015, 22:41
Hi and welcome! X
I am on levothyroxine for a underactive thyroid but have had no probs doing 5:2.. As long as i stick to it, i lose weight and suffer no ill effects as far as i know,tho ive read that people sh'd be cautious and not fast more than 14-16 hrs if they have hyperthyroidism. I DO fast longer..probably about 20 hrs between my pre fast evening meal and my 500 cal dinner on a fast day
4:3 at 1000 cals ive not heard of but its low cal and will lead to weight loss if youre careful the other days.
Its another option i guess but somebody more cluedup than me can no doubt give you a more informative answer than i can..hope they'll be along soon to help! X
Re: 4:3 for Hypothyroid?
27 Jan 2015, 22:48
Thank you, I'm glad to hear 5:2 is working for you, I am finding it very manageable, although 4:3 sounds more difficult even with higher calories.
Re: 4:3 for Hypothyroid?
28 Jan 2015, 01:38
I do 4:3 and find it easy(ish) to follow because of the rhythm. I don't know about fasting and hypothyroidism, but I just read that someone else here was going to try 800cals on fast days here: introduce-yourself-f1/yet-another-newbie-t13762.html
There's also some links in posts on that thread for more information on fasting and hypothyroidism.
Anyway, welcome and good luck!
Re: 4:3 for Hypothyroid?
28 Jan 2015, 02:35
Well I may be hypothyroid in about six months as I just had radioactive iodine to treat my hyperthyroid. So I've been reading up.

I have seen science that indicates prolonged fasting isn't helpful, but that 12-16 hours should be no problem, so I intend to do 16 hour fasts three days a week once I become hypothyroid. I'll probably aim for 750-1000 calories and see how I do on those days. My husband and I calculated out that at our BMIs/TDEEs, doing 3x1000 calories was for us about the same calorie deficit in a week as 2x500 calories (again, considering we are reasonably careful on our normal days and not binging).
Re: 4:3 for Hypothyroid?
28 Jan 2015, 08:30
Thank you for all the replies, It sounds like there are lots of different methods going on, I am trying to work out what will be best and I think it may take some trial and error. Tracieknits it sounds like you're going through it with your thyroid! Your eating plan sounds like the one I'm thinking of trying although I have done a 500 cal fast this week and may now do two 1000 cal days eating a late lunch/early dinner. for anyone who hasn't seen it the article I referred to in my OP is on here in the fasting library section, in the bit about fasting with medical conditions. I am very tired of feeling tired now and I hope to gain some energy from this way of eating.
Have a good day/night everyone ,depending on where you are :smile:
Re: 4:3 for Hypothyroid?
28 Jan 2015, 09:33

I've been recommended trying 800 for 2 days and normal, healthy balanced eating for the other 2 days. Have found a book called 800 Fasting diet or something like that which seems quite good. I guess you could quite easily adapt their plan to add another couple of 100 calories per day if 800 is too low for you. Good luck with finding the way that works for you. ... lorie+diet
Re: 4:3 for Hypothyroid?
28 Jan 2015, 11:50
I really don't think anyone needs to spend any money on fasting books, not even Dr. Mosley's. All the information anyone could need is available for free on the web.
Re: 4:3 for Hypothyroid?
28 Jan 2015, 13:57
You are probably right - there is a huge amount of information online. However, I was just struggling to find that much information online about the benefits of 800 calorie fasting and how it differs (if doing it well) from the 500 calorie fast. So thought I'd buy a book - didn't cost much!
Re: 4:3 for Hypothyroid?
28 Jan 2015, 17:01
I'm just wondering what the theory is for having 800 calories on fast days rather than 500? I'm hypothyroid too and am not having much luck losing so far(end of week 4).

I assuming the extra calories are of some benefit to us Hypos? :?:
Re: 4:3 for Hypothyroid?
28 Jan 2015, 17:28
I haven't read all the book yet - but I think its something to do with the thyroids link to metabolism and good fats promoting fat loss - also something to do with the circadian rhythm.
Re: 4:3 for Hypothyroid?
28 Jan 2015, 19:28
Here's the page on Thyroid disorders that @Carorees wrote up. ... disorders/

Yes, the thyroid very much follows a circadian rhythm. We have the lowest amount of T3 and highest amount of TSH in the morning, before we eat. If you are taking hormone replacement, this is why you take it first thing in the morning on an empty stomach. One good friend of mine found that simply making sure she kept her medication by her bed, taking it first thing on an empty stomach and waiting at least 1/2 hour to eat or drink anything other than water was all she needed to do to feel better and lose weight normally. Before doing this (she had been taking her medication later in the morning, with breakfast), she had no energy, was gaining weight way too easily and felt terrible.

From all of the things I've read on hypothyroid, the 800 calories/calorie composition in this book must be a guess. I haven't seen any studies about specific diets or specific calorie amounts targeting specifically hypothyroid people. It may be a good guess, but it's most likely a guess.

Most people looking to lose weight will do better by eating fewer carbs. Since too much protein is also a problem, it naturally follows that some increase in fat consumed is necessary, and healthier fat is always a better choice than hydrogenated oil. I don't generally go low-carb, but I do go low carb on fast days (although I'll make an exception for beans in a soup, like yummy black beans).
Re: 4:3 for Hypothyroid?
28 Jan 2015, 19:40
I think it is more to do with 800 calories being better for anyone with an autoimmune condition rather than specifically for hypothyroid sufferers. I will carry on researching and let you know what I can find (if anything!) x
Re: 4:3 for Hypothyroid?
28 Jan 2015, 19:50
Goodness me, I can't remember if I'm hypothyroid or the other side, but I think it's hypo and for that I take Levaxin 125/day. The dose has been steadily increased over the years and the symtoms that something is wrong is worse depression than normal and I sit and cry for myself :cry: .

But during these 6 years or something no doctor or pharmacy people have ever told me I ought to take the pill first thing in the morning or on empty stomach, so I take them along with another med round 10am And - it works.

I stick to 5:2 fast and most often it is 20 at least hours between my pre-fast dinner and my 500kcal one and - I lost 17kg even though. OK, I gained 3 during post op rehab and healing but I do hope that now that I'm back on track will loose them rather quickly. if anyone think I could loose those kg faster by changing the amount of hours between meals, please oh please tell.

Time to go to bed and read some, the newest Tom Clancy (written by another guy. How that adds up is beyond me, but the book is good).
Re: 4:3 for Hypothyroid?
28 Jan 2015, 20:02
@Wolfie thanks :-) That medicine is for hypo, which is the more common thyroid disorder. If in the future you find it's not working as well, try taking it first thing on an empty stomach. I can certainly see how hypo symptoms could feel like depression!

I'm glad to hear you're doing better!! good luck on losing the last 3 quickly :-)
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