A doctor highlights the often-overlooked connection between liver health and thyroid function. The liver plays a crucial role in converting inactive T4 thyroid hormone into its active T3 form, essential for bodily processes. Compromised liver function, due to factors like inflammation or fat accumulation, can impair this conversion, leading to hypothyroid symptoms even with normal thyroid lab results. Additionally, liver stress can increase inactive reverse T3, further hindering thyroid hormone effectiveness and causing symptoms like fatigue and weight gain.