Subcutaneous Layer

The first layer below the cutaneous membrane is called the subcutaneous layer. It is also known as the hypodermis and superficial fascia. Although this layer helps stabilize the integumentary system and shares some characteristics, it is not technically a part of the integumentary system.

Within the subcutaneous layer, you can find major blood vessels, adipose tissue, connective tissue, lymphatic vessels, nerves, and glands.

The function of the hypodermis layer is to protect vital organs that are deeper in your body. The hypodermis is also heavily affected based on your sex and the hormones you produce. An increased concentration creates a hypodermis that is thicker in areas like the back, arms, and shoulders. If you have a higher concentration of estrogen then you can expect the hypodermis to be thicker in the butt, thighs, and hips.

The hypodermis is also a well-known area for medical injections. Things such as the hypodermic needle and subcutaneous injections target this area for the contents within this layer.