Brush Construction. 1  Selected hairs are separated into small piles. Each pile is combed to remove curled or cut hairs. 2  Hair piles are bundled, wrapped in newspaper and tied with string. The hair bundle is boiled in water to remove oils and straighten the hair. 3  A single brush can contain several different hair lengths.
1 The thyroid gland plays a primary role in your energy level, muscle growth, metabolic rate, and brain function. 2  Hypothyroidism is a common disorder in which the bodyâs ability to produce enough thyroid hormone is insufficient.hyroid Hormones. 1  The thyroid gland plays a primary role in your energy level, muscle growth, metabolic rate, and brain function. 2  Hypothyroidism is a common disorder in which the bodyâs ability to produce enough thyroid hormone is insufficient.
Normal thyroid function is regulated by the pituitary gland. The pituitary makes a hormone called TSH that causes the thyroid gland to make thyroid hormone for the body. TSH also promotes growth of the thyroid gland and probably of thyroid cancer cells.The level of TSH, in turn, is regulated by how much thyroid hormone is in the blood.he pituitary makes a hormone called TSH that causes the thyroid gland to make thyroid hormone for the body. TSH also promotes growth of the thyroid gland and probably of thyroid cancer cells.