Laser Technician (International Board of Electrologist Certification) IBEC Board Exam

Which factor can change the classification of body hair from vellus to terminal?

1. Age

2. Hormonal changes

3. Diet

4. Genetics

The correct answer is: Hormonal changes

Hormonal changes play a significant role in the transition of body hair classification from vellus to terminal hair. Vellus hair is fine, short, and lightly pigmented, often referred to as "peach fuzz," while terminal hair is thicker, longer, and more pigmented, typically found on the scalp, in the beard area, and in the underarm and pubic regions. During puberty, hormonal changes, particularly increases in androgens like testosterone, stimulate the hair follicles to transition from vellus to terminal hair in certain areas of the body. This process is influenced by the hair follicle's sensitivity to these hormones. In adult life, hormonal fluctuations such as those occurring during pregnancy or hormonal therapies can also lead to changes in hair classification. While age, diet, and genetics can impact hair growth and characteristics, they do not directly cause the transformation from vellus to terminal hair. Age can influence hair density and thickness over time, diet can affect overall hair health but not fundamentally alter its type, and genetics determines the pattern of hair distribution and growth quality, but hormonal changes are the primary driver of the change from vellus to terminal hair classification.