Vellus hair references short and fine hairs on the body or scalp that are commonly referred to as “peach fuzz” or baby hair. In fact, this type of hair is more observable on women and children than men. This is because vellus hairs are translucent and easily concealed by the thicker terminal hairs. Babies especially have an abundance of this type of hair. During puberty, many vellus hairs transform into stronger and move easily seen terminal hairs. The origins of the word “vellus” roughly translates into “fleece” or “wool”.
These hairs are much shorter than normal, and their follicles do not have sebaceous glands. The hair shaft is quite narrow, sometimes more than the root sheath itself. The hair bulb is located higher than most hair follicles, and follicle itself is not very deep. Since this type of hair does not have a sebaceous gland, and terminal hairs do not come in until puberty, some hair specialists theorize that sebaceous glands are what causes the onset of acne during puberty.
The following diseases are known to cause the following symptoms relating to vellus hairs: