Intermittent fasting affecting thyroid values

[Alex_p]

For the last few months (around 4), I’ve been doing intermittent fasting, because I’ve read about the benefits of taking a break from eating. I eat for about 8 hours and fast for around 16 hours. My latest thyroid test results have shown a slight decrease in both FT4 and FT3. I’ve read somewhere that it’s not recommended to do intermittent fasting if you have Hashimoto’s, is that true? I haven’t changed anything lately, I take my usual supplements. So my question is: could IF contribute to lower FT3 and FT4?

[Sleepman]

I do the same fasting and I did not find anything written, to say its not ideal with hashi. I am just about over prediabetes now

[TiggerMe Ambassador]

I think you are right it is a known thing that if you reduce carbs it effects uptake and conversion of thyroid hormones, I find I struggle if I go beyond 12 hours fasting

[Luckyclaire]

I used to fast before thyroid treatment, and have experimented with it since. I have seen in research that lower carbs and fasting effect conversation of T4 to T3, so lower T3. The general picture seems to be that it effects individuals differently, some coping fine with it and other getting lots of unhelpful effects. I read some researched (based on very poorly intensive care patients) that the lowering of T3 was a natural proventative feedback loop to reduced muscle wastage when fasting/low carbs. In some people it seems to really stress the system and cause problems. It is a big no-no if you have cortisol issues. Personally, it made me feel poorly after about ten days, and no longer suits me. I do a 12/12 split now, and eat carbs more than I used to, but still not excessively

[Hidden in reply to Luckyclaire]

I had the same experience. I was doing IF three days a week, 16/8 split, and after a few weeks it literally made me unwell. I was really disappointed but it definitely doesn't agree with my system. I am long term hypothyroid but don't have Hashi's as far as I know, but I do have coeliac disease.

[Blissful]

I have Hashis - I've been using IF for a decade, (I kind of stumbled into it after I had a small pneumonia and couldn't eat at all for about a month). I eat exactly what I want to eat during my (mostly) 8 hour window.

After a few months I had a "eureka" moment and realised that I'd always felt the best eating that way (but when I was married I went with the flow as it were because it was easier I suppose and it's only with hindsight and reintroducing IF that I understood how well it suited me.

I can't help with whether IF might downgrade your FT4 and FT3 numbers because for me they stayed pretty much the same (replacement is equivalent to daily 78mcg T4 and 12.5 T3).

[CoeliacMum1]

Yes there are some nutritionists and evidence that Intermittent fasting (IF) isn’t good for all with a variety of autoimmune disorders as someone also pointed out which I think is more common knowledge if we go low carb it can throw few problems.

I think generally under guidance there is probably away around it, it is just finding what is best for you and not do the more intense shortened window of eating along with still getting the right carbs that works for you …our metabolism and hormone status along with sleep, lifestyle stresses play such important role.

I follow on Instagram Dr Sara Gottfried and Dr Jolene Brighten for hormone related medical things along with Pippa Campbell, Emma Bardwell and Tanya Borowski as they’re more hormone related nutritional specialists.

IF definitely has helped many but may not be for all., we all have different triggers so if it’s causing you symptoms, even our menstrual cycle has impacts.

drbrighten.com/intermittent...

[Alex_p in reply to CoeliacMum1]

I wouldn’t go with a shorter window for eating, I don’t think I could do it, I would get very hungry and eat too much after. I think I eat enough carbs, I mainly focus on getting enough fibre as it helps with constipation. Getting enough protein is a challenge though.

[arTistapple]

I began taking my thyroxine at night. This meant no snacking for four hours before. So fasting for approximately 15 hours per day. I like this arrangement. After months of doing it, I have finally lost some weight. Perhaps not a lot.

I have also been attempting Gluten Free. This has been odd as I am now pretty sure that Gluten Free ‘goods’, particularly bread, are very bad for me. I am thinking here that something along the lines of ‘Ultra processed food’ is the problem. I have had problems with ultra processed food for as far back as I can remember and shop bought GF bread is a classic source of Ultra processed food in my observation.

My status is ‘mixed’ at present. Happy to have lost weight. Concerned about looking rather quickly older. Lost that (pretend) healthy look. Feel better about getting my body about a bit better. Feel better about not bursting out of my clothes.

However thyroid status remains far from optimal.

I will keep on with this regime for the benefits and see how it goes. I have raised my Levo from 100mcgs to 106.25mcgs. That’s small I know but have had trouble raising either T4 or T3 in the past.

[Hidden in reply to arTistapple]

it's good to hear someone talking about the unhealthy, highly processed foods that most shop bought GF foods are. I've been coeliac for 45+ yrs - 20 undiagnosed and 25 since diagnosis and I never ate these kind of foods before diagnosis. I was a 'stone ground whole wheat' kind of girl and there's very few, if any, equivalents in GF world. It dismays me to see this current fad for going GF. So many people assume that GF means healthy, which it certainly doesn't

Apart from anything else, rice contains arsenic, which is at tolerable levels when eating actual rice, but so many GF products are made of rice flour (because cheap) which has more concentrated levels of arsenic and there is growing concern that coeliacs are being exposed to unacceptible levels of this toxin.

[arTistapple in reply to Hidden]

I had forgotten that piece of info about rice. I am just getting into the swing of this GF thing. Arsenic would definitely worsen gut problems. Me. I must say I prefer real food. So I will continue on my GF travels but without the ultra processed contribution!

[CoeliacMum1 in reply to Hidden]

Absolutely… the free from fairy highlights arsenic in rice in the past (although it’s in many other things also😵‍💫) and how much us coeliacs and those who prefer to go gluten free for their own reasons are encountering higher levels than in a “normal” diet and made a rice free flour and recipes too, unfortunately I don’t get on with theses emulsifiers and gums that are often added in place to make the product gluten like in structure… so for me I don’t eat much processed food and pasta I choose the higher fibre ones whenever I can …. Definitely not reliant on them but rice does appear a lot in my diet overall as love curries and Asian food … I tend to try various flours and grains to mix it up a bit for baking and bread etc… although most foods do contain some.

[Hidden in reply to CoeliacMum1]

I really liked her flour mix and am sad that she no longer offers it, though I totallly understand her reasons.

[CoeliacMum1 in reply to Hidden]

Oh I thought she still did it… I get emails from her still but to be honest not took too much notice 🫣 as I didn’t use it but as her background is biochemistry was interested in her view generally on things.

[CoeliacMum1 in reply to Hidden]

Re Free From Fairy

I was surprised to find no psyllium husk I thought she had mentioned that before so discounted her flour… maybe it’s added in for various other things in recipes.

Here is screenshot but you can easily find it and more on her website the flour mix ingredients.

Free From Fairy, rice free gluten free flour mix…

[Hidden in reply to CoeliacMum1]

Thank you, yes, I have the recipe but that's a huge hassle trying to find all those types of flours that are certified GF (ie no cross contamination). I think I tried once but gave up.

[CoeliacMum1 in reply to Hidden]

I’ve not used sorghum to know much about that one, but can see it on Amazon, you can get the others I got mine on Ocado/Amazon and definitely certified I obviously wouldn’t use anything other… I use Noglu, a French recipe with gram flour buckwheat but does use rice flour too but I’m tempted to try this now.

[Lovecake]

My endo recommended fasting to lose weight! It worked for him……..but he doesn’t have a thyroid problem. 🤦🏻‍♀️

It doesn’t suit me. I need to eat regularly. Although, if I’m not hungry, then I don’t eat for the sake of it. As you would expect, when my thyroid levels are the right level for me I eat less.

[arTistapple in reply to Lovecake]

I wonder what the doctor meant by it though. A good guess would be NOTHING AT ALL.

It sounds to me you have a good system worked out for yourself. Steam on clever girl.

[Lovecake in reply to arTistapple]

I think he was just pleased with himself for losing weight 😂

Asked me if my weight had gone up a bit (it had) and that was his recommendation. Ignoring the fact my thyroid levels are a bit low because my TSH is 0.01 (I take some T3). I only use him for getting my T3 and to occasionally ask my doctor to do some extra blood tests. He was handy for requesting a DEXA scan too, so I’ll stay with him a bit longer 😉

[arTistapple in reply to Lovecake]

Yup. It seems many of us just have to learn to use the system in place, with our antenna on full blast and with a view to helping ourselves, as they seem to be unable to offer any genuine help.

[Lovecake in reply to arTistapple]

Definitely. And I pay for his expertise, but I pretend I’m listening and do what I’ve learned over the years instead 🤓

[CoeliacMum1 in reply to Lovecake]

😂 love this 🤭

[TiggerMe Ambassador in reply to Lovecake]

If you feel you need a follow up Dexa and you're anywhere near a Nuffield Health Centre you can self refer... guessing the other private clinics are the same?

[Lovecake in reply to TiggerMe]

Thanks. My GP listens to him (she is lovely). And therefore I didn’t have to pay this time. She has scheduled a retest in 2 years.

I think the nhs sent me to a Nuffield place. They seem to use private healthcare to either plug gaps or save them having expensive equipment in buildings they don’t need to be paying for.

[Alex_p in reply to Lovecake]

IF has not helped me lose any weight. That’s probably because I’m not actually eating less calories. But it’s not why I started it anyway. I do find that I don’t get hungry in the evening anymore so my body has probably adjusted to the new eating schedule.

[Sleepman]

great discussion.

I am IF as I said near the top. Tend to not eat after 8 till 11:30 to 12:00. It is weird, I do not feel hungry till I break my fast ! If travelling and working away it can be 5 PM before I eat, but tend to overeat then the next day.

I did not go very low carb even though I have prediabetes, I asked on here about facts to back up the low conversion effect of low carbs but do not remember seeing anything clear cut. I found keto hard to stick to after a few months which is ultra low carbs.

+1 for avoiding chemical GF breads and stuff - I am hashi and gluten intolerant

I looked at arsenic in rice a while back and convinced myself it is actually ok. I do eat even more now

I think a little T3 has helped me shed weight. I need it as T3 is low.

[Revsie]

hi Alex, no idea about the effect of FT3 or FT4, but I’ve been doing intermittent fasting for over 2 years now. I’m 2.5 stone lighter and my metabolism seems to have reset itself to my pre under active thyroid diagnosis, I have nothing but good things to say about IF, it’s been a miracle cure for my weight ….and I haven’t been advised I need to alter my thyroid meds by my endo?