This is the skin’s energy reserve.
It is composed of loose connective tissue known as white adipose tissue. This, in turn, is made up of cells known as adipocytes that are programmed to store fatty acids. They are clumped together with the papillae adiposae and separated by fibrous walls of collagen and elastin.
Like a mattress, the hypodermis helps give the skin its plasticity, acting as a shock absorber and heat insulator. Its thickness varies depending on the individual and the area of the body in question.