How your hormones might be controlling your mind

Again, the reason for thyroid hormone’s impact on mood isn’t known, but one theory is that T3 in particular may increase levels of serotonin and dopamine in the brain, or enhance the sensitivity of receptors for these neurotransmitters. Thyroid hormone receptors are also prevalent in brain regions heavily involved in mood regulation.

New treatments 

The hope is that this new knowledge of hormones, and their mood-altering effects, will trickle down into new treatments. There are signs this is beginning to happen, with a drug called Brexanolone, which mimics the hormone allopregnanolone, proving very effective at treating post-partum depression.

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There is also some evidence that if you have lower levels of testosterone, then taking testosterone supplements alongside certain antidepressants can make them more effective. Studies show that oestrogen therapy, including hormone replacement therapy (HRT), can also help improve the mood of some but not all women going through perimenopause and menopause. 

Hormonal birth control, meanwhile, can work wonders for some women with PMDD, however it can make symptoms worse for others, highlighting how the search for new treatments is hampered by the fact that we still don’t understand exactly why some people are so sensitive to hormonal fluctuations, while others aren’t.