It might make a geograghical difference. Like places that get 20 to 30 below zero in winter but still get 90's in summer.
The human body and metabolism wants to change like all other mammals.
Apparently some people do this. But I have never read it hear - in a book only.
16yrs on thyroid med and I have never had to adjust for any type of seasonal reason.
I am also pretty sure my doctor would not support this unless the TSH level says otherwise. Yep, my dr. goes by the TSH level only. I really have not had any issues with my dosage though, so I can't complain.