I found this paper whilst searching for answers on why I have peaks and troughs of what feels like cortisol throughout the day. It has quite a bit of scientific info but if you scroll through you’ll find hormone specific results.
There does seem to be an impact from intermittent fasting so hopefully of some use to someone.
Interesting, a whole report suggesting there isn't enough data... is it me?
I've tried eating in a 12 hour window the last 2 weeks (and going lower carb paleo than I was before) inspired by Dr Sarah Myhills new book.
I have lost over just under a kilo in 2 weeks, have more energy, fewer cravings, wake up ravenous but sleep better.
I tried the 5:2 idea before I was diagnosed and it was a disaster, I over ate for 5 days and starved for 2, I was cranky and wobbly and no, never again.
A friend who is Hashi diagnosed but has refused thyroid hormone blocking and replacement for over 10 years relies on intermittent fasting, juice fasts and water fasts to force her body into balance, she is a natural healer herself and very experimental, but it seems to have worked for her for 10 years although she is now leaning towards taking Levo now she's the other side of 50 and is on HRT (bioidentical).
I just saw your post here Jamima, thought I’d add my 2 pence. For whatever it is worth, I did a ketogenic diet for 18 months and the effect is had on my adrenal function has been devastating. Most likely because my thyroid function initially was poor.
Ketosis/IF drives cortisol up because it plays a vital role in gluconeogenesis (making sugar from protein) so the adrenals end up being over recruited, eventually they may fail. It’s tricky because on the surface it can appear an appealing option for those with adrenal fatigue since cortisol has to rise to meet ketogenesis demand. So one thinks YAY, MY CORTISOL IS NORMALISING but really it’s a waiting game to see how long it will be able to hold you up before they sputter out and youre in trouble. There are also additional short term benefits like reduction in inflammation, suppression of grehlin (hunger hormones), blood sugar stabilisation from ketones and weight loss since glucose-dominated metabolism means carrying much more fluid - all of these things can make people jump on the keto train and shout the benefits from the treetops. Longer term it is not wise, there are no studies that tell us if it’s safe and only incidences of epileptic children put on the diet developing kidney issues (altho this is also maybe linked to the utter crap they are fed, like their fat source is seed oils and their protein comes out of a carton 😟). I’d really be weary if dealing with adrenal fragility. I’d go as far as to say that Dr Myhill is being very naive in blanket recommending the ketogenic diet to everyone, especially thyroid compromised people.
I think it is a bit like running your broken house off a generator. Fixing the house (thyroid/adrenal function) is really what you need to do.
Thank you. I no longer use IF and never tried Keto. I 1st ran into problems with IF around 4/5 years ago when I was very stressed running 2 businesses and caring for a bed bound partner after 3 knee operations. That time was when, I’m hindsight, I started to feel ‘hypo’ symptoms although I didn’t know it at the time. I was happily using hrt and keeping all the plates spinning. AND THEN THE WHEELS CAME OFF. I haven’t recovered since although I’m better than I was 2-3 years ago when I simply couldn’t get off the sofa during the day. I think my thyroid or pituitary was struggling and I kept pushing on buoyed up by HRT until eventually the adrenals said NOPE. I had lower back pain, joint pain to the point of not being able to put on a coat/do up my bra, I ticked all the low cortisol boxes and quite a few of the thyroid. And that’s when I started to look for help. It’s been an interesting journey but I can’t fast, I get terrible low sugar symptoms.
18:6 intermittent fasting diet
Weight loss and hypothyroid: intermittent fasting?
High cortisol level results 
Ashwagandha for cortisol levels
No Action On High Cortisol Levels
