T4 is a Thyroid hormone which helps control rate of the energy that a human body use. T4 is also called as Thyroxine. TSH stimulates the Thyroid gland to produce T4 and T3 ( Tri- iodothyronine).
TSH is produced in a pituitary gland. TSH also helps to maintain the thyroid level in the body by reversing it with the help of Thyrotropin hormone produced by Hypothalamus. When the thyroid gland, pituitary gland and hypothalamus functions and sync up together the thyroid level is maintained in the human body. If Thyroid gland releases more T4 and T3 it results in Hyperthyroidism results in symptoms like Increased heart rate, Weightloss, weakness, tremor, Anxiety, and irritation of eyes and skin. If TSH is produced more it reverses the thyroid hormones (T4 and T3) results in Hypothyroidism results in symptoms like weight gain, cold intolerance, Fatigue and menstrual irregularity.