256 ‒ The endocrine system: exploring thyroid, adrenal, and sex hormones | Peter Attia, M.D.

Summary

In episode 256 of Peter Attia's podcast, the discussion revolves around the endocrine system, focusing on the thyroid, adrenal, and sex hormones.

The thyroid system is regulated by the thyroid-stimulating hormone (TSH) which is produced by the anterior pituitary gland. TSH prompts the thyroid gland to produce T4 (inactive) and a lesser amount of T3 (active). This process is regulated by the hypothalamus via the TRH hormone. T4 is converted into active T3 through deiodinases (D1, D2, and D3). D1 and D2 create T3, while D3 creates reverse T3, which may indicate inflammation, illness, or nutrient shortage. Treatment for hypothyroidism involves administering T4, T3, or a combination of both, with desiccated thyroid serving as an alternative option.

The adrenal system evaluation involves measuring free cortisol, free cortisone, and their metabolites via the Dutch test, as blood tests for cortisol tend to be insufficient. It is important to understand that "adrenal fatigue" is often caused by other factors such as obesity, insulin resistance, and inflammation. Treatment options include addressing these underlying factors and the possibility of using supplements like licorice root.

Understanding hormonal changes during the menstrual cycle is vital to comprehend female sex hormones. Hormonal imbalances can lead to various issues in women, like infertility and PCOS. The cycle involves follicle-stimulating hormone (FSH) and luteinizing hormone (LH) secreted from the pituitary gland, with their fluctuations dictating different phases. Treatment options for hormonal imbalances can range from lifestyle changes and hormonal treatments to surgical interventions.

As women approach menopause, FSH and estradiol levels are monitored to identify signs of menopause. Hormone replacement therapy can begin during the perimenopausal transition to manage symptoms.

In the male hormone system, GnRH, LH, and FSH play similar roles as in the female system. Testosterone monitoring is essential as it is mainly bound to sex hormone-binding globulin (SHBG) and albumin. Androgen receptors play a role in binding testosterone and dihydrotestosterone (DHT). Testosterone replacement therapy necessitates assessing both biochemical and symptomatic cases before proceeding with treatment, which requires regular monitoring of symptoms and hormone levels to ensure efficacy. Treatment options include exogenous testosterone, HCG injections, and Clomid. The podcast episode serves as an informative source to better understand the dynamic interplay of hormones within the endocrine system.