Familial Longevity Is Associated With Decreased Thyroid Function

[Queequeg]

Wrong food/macros for IF, no run-in period to put both groups in same metabolic situation. No salt or other mineral addition.

Not so sure about that. The macro breakdown is a very typical diet recommendation. What evidence do you have that IF would work any differently with another macro profile?
Both groups are already on the same metabolic baseline as they are randomly assigned. This averages out any differences among individuals. The experiment was to see the effect of an 8 week intervention.
It doesnt give a breakdown for salt or mineral content but the fact that the control group didnt show any changes tells us that the diet was sufficient in all macros and micros.

I think this was a pretty well run study and is a real wake up call to those who think IF is a healthy choice.

 

[rei]

You need sufficient amounts of saturated fat to do IF and you dont want more carbs than what your glycogen stores can take. You need to make the metabolic switch unless you did IF from before, this should happen during the run-in period. During this period you should not stress yourself by training anywhere near as hard as normally and also supply enough salts. And the correct transition from 3 meals a day to IF is not like they did, but first few days 2 meals, then once it feels easy you start 1 eating window. This way there is really no stress.

The stress from training while also making the switch ramping up fat metabolism is probably the reason why thyroid activity dropped. Copious amounts of PUFA was freed and it ended up knocking the level down.

 

[Queequeg]

You need sufficient amounts of saturated fat to do IF and you dont want more carbs than what your glycogen stores can take. You need to make the metabolic switch unless you did IF from before, this should happen during the run-in period. During this period you should not stress yourself by training anywhere near as hard as normally and also supply enough salts. And the correct transition from 3 meals a day to IF is not like they did, but first few days 2 meals, then once it feels easy you start 1 eating window. This way there is really no stress.

The stress from training while also making the switch ramping up fat metabolism is probably the reason why thyroid activity dropped. Copious amounts of PUFA was freed and it ended up knocking the level down.

do you have any studies that confirm what you're claiming? Otherwise sounds like a lot of bro science.
As for the proper transition period, they only removed one meal per day, 3 to 2, so based on your theory there was no need for a transition period.
The fact that fasting lowers thyroid function shouldn't be that surprising. It is a survival adaptation to lower metabolism when food is scarce.

 

[rei]

No, i don't know of studies comparing different methods to transition into IF. Until then we need to go by theory. And what i wrote is common sense to minimize stress and what people tend to agree is the right way to do it..

http://www.jpma.org.pk/full_article_text.php?article_id=5320
It does not lower thyroid unless you are doing everything you can to make it happen by your study design. IF is actually widely known to increase the metabolic rate.

 

[Whichway?]

I worked in a research lab which used the model organism C. elegans and we did some lifespan studies. We found changes in metabolism that lowered metabolic output seemed to increase longevity. My professor used to think that lower metabolism as you aged might be protective of other issues like cancer. He thought it was a trade off.