Sebum and sweat are secretions of our body and are secreted by its special type of glands. Sweat is produced by sweat glands and sebum is produced by sebaceous glands. Both are present in the skin layer and the sebum and sweat producing glands are mainly present near the hair follicles. Somehow similar to each other they still differ in many aspects like, in the type of secretions for example; sebum is mainly made up of an oily or waxy substance, while sweat consists of water and sodium chloride. Both secretions help maintain body temperature.
What is sweat?
Sweat is produced by the sweat gland which is also called the apocrine gland, a type of exocrine gland. Apocrine has coiled tubules and a duct that helps excrete secretions from the gland near the hair follicle. These glands are present near the junction of the subcutaneous fat and the dermis. Sweat-producing glands are found in specific regions of the body such as the armpits, areola, nipples, eyelids, ear canal, nostrils, external genitalia, and perianal region. Apocrine gland secretion is periodic, and the gland secretes an oily fluid rich in lipids, steroids, and proteins. Sweat maintains body temperature and also excretes waste products through the skin. Sweat is watery in nature and is made up of water, carbohydrates, proteins, waste material and sodium chloride. Sweat is initially odourless, but as soon as it comes into contact with bacteria, it begins to produce an odor. Sweat is mildly acidic in nature and has a pH of 6-7.5. The 5-month-old human fetus has sweat glands distributed throughout the body, which after birth are located in specific regions such as the axillae, areola, perianal and external genitalia.
Sebum is produced by sebaceous glands which are microscopic holocrine glands, a type of exocrine gland present in the epidermis. Sebum helps lubricate and control temperature. It also waterproofs the skin and hair. Sebaceous glands are present in all parts of our body, especially the face and scalp. But our palms and soles lack sebaceous glands. The sebaceous glands that are present in different parts of our body have different names like areolar glands that surround the nipples, Meibomian gland that are present in the eyelids, and Fordyce spots on the cheeks, gums, and lips. Sebaceous glands are found in the hairy regions of the body where their excretory ducts are connected to hair follicles. The sebaceous glands that are connected to the hair follicles are called the pilosebaceous unit. The pilosebaceous unit consists of hair, hair follicle, arrector pilli muscle, and sebaceous gland. Sebum is composed of wax esters, triglycerides, squalene, and fat-producing metabolites. Wax and squalene are only secreted by the sebaceous glands in our body. Like sweat, sebum is also initially odourless, and when it comes into contact with bacteria it produces an odour. The sebaceous glands of the human fetus during the last 3 months begin to produce a protective covering called vernix caseosa. Vernix caseosa, a waxy layer that surrounds the fetus and protects it from amniotic fluid. The sebaceous glands of the human fetus during the last 3 months begin to produce a protective covering called vernix caseosa. Vernix caseosa, a waxy layer that surrounds the fetus and protects it from amniotic fluid. The sebaceous glands of the human fetus during the last 3 months begin to produce a protective covering called vernix caseosa. Vernix caseosa, a waxy layer that surrounds the fetus and protects it from amniotic fluid.
- Sweat is produced by the apocrine gland while sebum is produced by the holocrine gland. Apocrine and holocrine are the types of exocrine gland.
- Sweat is mainly made up of water, salts, and waste products, while sebum is oily and waxy in nature.
- Sweat helps thermoregulate the body while sebum produces a lubricating, oily layer that slows water evaporation and helps fight dehydration.
- Sweat glands are present only in specific regions of the body such as eyelids, ears, armpits, areola, and external genitalia, while sebaceous glands are present throughout the body except the palms of the hands and the soles of the feet.