Do most women gain weight after thyroidectomy and do you recommend radio active therapy afterwards.

6 cm nodule on thyroid pressing on trachea- removed and frozen section was negative but bx showed small amount papillary cancer and all lymph nodes were negative. Had thyroidectomy and back to work in three days. tsh wnl t4 wnl (on synthroid) recommened via endocrinologist to have radioactive iodine therapy.