Which symptom is commonly associated with hyperthyroidism?

Heat intolerance is a hallmark symptom of hyperthyroidism due to the overproduction of thyroid hormones, which significantly increase metabolic activity in the body. This heightened metabolism elevates energy expenditure and generates more heat, leading to discomfort in warm environments or during physical exertion. Individuals may also experience excessive sweating and an increased sensitivity to heat as their body struggles to cope with the excess thermal energy, which is characteristic of this condition.

In contrast, weight gain, bradycardia (slow heart rate), and constipation are typically associated with hypothyroidism, where decreased thyroid hormone levels lead to a slower metabolism, weight retention, a slower heart rate, and reduced gastrointestinal motility. Understanding these distinctions helps in the accurate identification and management of thyroid-related disorders.