	Page 34 -- SPECIAL SKIN STRUCTURES

Causes of cellulite

The dreaded cellulite is the result of genetically determined deposition of fat from the teens onwards.

There are no magic cellulite treatment remedies for selective cellulite removal. It can only be reduced as part of an overall weight reduction program, together with cutting back on calorie intake and increasing exercise, although some fruit acid creams may help to make cellulite temporarily less obvious.

Special skin structures

The skin contains certain important structures with special functions. The lips are specially developed as sense organs. The sweat glands help to regulate body temperature
(see page 41). Most of the hairs on a human body have no real function and are a relic of when our ancestors needed warmer 'coats'.

The sebaceous glands

Sebaceous glands are part of the tiny structures - hair follicles - that generate hairs. These glands produce oil, or sebum, which is a mixture of waxes and fats. The glands empty through minute tubes called ducts. Sebaceous glands occur in the skin of every part of the body except on the palms and soles.

Sebaceous glands grow as part of the hair follicles. They produce sebum, which helps to protect the skin and lubricates the hair shaft.

   Sebum is secreted through the sebaceous duct into the hair follicle. It forms a mixture with the watery secretion of sweat,
which covers the skin and spreads along the hair. The mixture of fat and water forms a natural oil-in-water emulsion (see pages 100-1) which may have a protecting action on the hair. It also kills some fungi that grow on the scalp.
   Sebum is slightly acidic (pH between 4.2 and 5.6), which may be why people sometimes refer to the 'acid mantle' of the skin. This is a somewhat misleading expression in that it could wrongly suggest an impenetrable barrier. Skin is in fact permeable in both directions.
  In both sexes the sebaceous glands are strongly influenced by male hormones, and are most sensitive to these at puberty, particularly on the face and trunk (the acne areas, see pages 55-6).