11. Weight Loss
Hyperthyroidism is a metabolic disorder in which the endocrine thyroid gland produces significantly more thyroid hormones, i.e., TSH, T3, and T4 than the body needs. This influx of hormones results in a dramatic increase in the body’s basal metabolic rate and thus increases the body’s energy requirements. Consequently, patients use the energy they receive from food much faster than normal, and so they frequently lose large amounts of weight despite not doing any extra physical activity.