Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Hashimoto thyroiditis ?
    ### Response:
    Hashimoto thyroiditis is a condition that affects the function of the thyroid, which is a butterfly-shaped gland in the lower neck. The thyroid makes hormones that help regulate a wide variety of critical body functions. For example, thyroid hormones influence growth and development, body temperature, heart rate, menstrual cycles, and weight.
    