Hypothyroidism? Hyperthyroidism? January is Thyroid Awareness Month and Healia would like to help you understand the difference between the two most common thyroid problems– hypothyroidism and hyperthyroidism.

The most common thyroid problems involve abnormal production of thyroid hormones. According to the National Institutes of Health (NIH), hypothyroidism occurs when the thyroid gland is not active enough. This condition is far more common than hyperthyroidism and can make you gain weight, feel fatigued, and have difficulty dealing with cold temperatures.

If your thyroid is too active, it makes more thyroid hormones than your body needs. This condition is called hyperthyroidism. Too much thyroid hormone can make you lose weight, speed up your heart rate, and make you very sensitive to heat.