What effect does hypothyroidism have on heart rate?

Hypothyroidism is characterized by an underactive thyroid gland, which results in lower levels of thyroid hormones in the body. These hormones, particularly thyroxine (T4) and triiodothyronine (T3), play a significant role in regulating metabolism, including the function of the cardiovascular system.

In individuals with hypothyroidism, the decrease in thyroid hormones leads to a slowing down of metabolic processes. As a result, this can cause a decrease in heart rate, known medically as bradycardia. The heart rate often falls below the normal range, which is typically 60 to 100 beats per minute in adults.

In summary, the correct response is that hypothyroidism decreases the heart rate due to the reduced metabolic activity caused by insufficient thyroid hormone levels.