My colleague took part in research for a paper investigating the TSH levels of euthyroid
women trying to concieve
and their TSH was between 0.9
and 1.7, this is in the normal population.
I am hypothyroid myself and my TSH before treatment was 4.5, classed as borderline hypo, but I had all the symptoms and very high antibody levels, I couldn't stay awake, and even when awake the brain fog was terrible. Thyroxine made me feel human again.