Robert Whitfield MD explains how thyroid hormones control energy, brain function, and libido. T4 is inactive until converted to T3, but inflammation, high cortisol, and nutrient gaps block that conversion, leaving women with low-thyroid symptoms despite normal lab tests.
So that's the one that tells us to burn more calories and have more energy and keep our brain sharp and have a little bit of libido and keep our skin, hair, and nails healthy and our bowels moving. So that hormone is so, so important. But inflammation, cortisol problems, nutrient deficiencies, imbalances in the bacteria in our gut, there's a whole list of things that interfere with us being able to convert that T4 Pro hormone into the active T3 that we need. And so for so many women, they have all symptoms of low thyroid because they're not. They don't have the active thyroid hormone they need. But that's not the one that doctors are measuring. We just measure the other ones, and they look fine. So we're told that everything is normal, and then we just feel poorly.
