What substance do eccrine glands primarily produce?

Eccrine glands primarily produce sweat, which is crucial for thermoregulation and maintaining body temperature. These glands are distributed all over the body, particularly on the palms, soles of the feet, and forehead. When the body temperature rises, eccrine glands secrete a watery fluid that evaporates from the skin's surface, aiding in cooling the body. This type of sweat is typically composed of water, electrolytes, and small amounts of metabolic waste.

In contrast to other substances, such as sebum, which is produced by sebaceous glands to lubricate and protect the skin, and melanin, which is a pigment produced by melanocytes that gives color to the skin, sweat plays a unique role in thermoregulation. Collagen, on the other hand, is a structural protein found in the dermis, contributing to skin strength and elasticity, but is not produced by eccrine glands. Understanding the function and production of sweat from eccrine glands is essential for grasping the broader context of skin physiology and homeostasis.