What causes lid lag in hypothyroidism?

In hypothyroidism, the production of thyroid hormones is reduced, which leads to a slowing down of many bodily functions. This includes the muscles responsible for eyelid movement, resulting in a delayed return of the upper eyelid (lid lag) when looking down and then back up.

Thyroid hormones play a significant role in regulating the growth and function of various tissues and muscles in the body, including those involved in eyelid movement. When thyroid hormone levels are low, as in hypothyroidism, the function of these muscles is impaired. The weakened or sluggish muscles affect the eyelid's ability to move back to its original position promptly after looking down, causing noticeable lid lag.

Therefore, lid lag can be an indication of an underlying thyroid problem, specifically hypothyroidism, making it essential to consult a healthcare professional for further evaluation and management.