Subcutaneous adipose tissue may be referred to more simply as the layer of fat directly beneath one's skin that exists alongside blood vessels and nerves. The human body takes excess energy and stores it as fats for later use during times of exertion or reduced nutrient intake. Subcutaneous fats are white in appearance and serve to insulate the body against heat loss and to protect and cushion the skeleton against injury.

Fat is also essential in carrying out biological processes, including the manufacture of certain hormones and has the ability to remove toxins from the blood stream and store them. This allows the body to deal with the toxin at a slower rate and helps to keep our vital organs, particularly the liver and kidneys, from becoming overwhelmed. In addition, adipose tissue plays a vital role in the synthesis of certain vitamins, such as A, E, D, and K. Subcutaneous adipose tissue is vital to the human body, but in excessive quantities may have adverse effects on health.

In cases of rapid weight gain, the skin may bear stretch marks from being forced to expand too quickly. In women, subcutaneous fats are most often deposited onto the hips, thighs, and buttocks. These areas are commonly plagued by the appearance of cellulite, which is the uneven distribution of fat pockets, resulting in a lumpy appearance of the skin. Though not yet proven, some evidence suggests that cellulite may contain higher levels of stored toxins than normal subcutaneous fatty layers. In men, excess fat stores typically accumulate around the abdominal area. Unfortunately, research has shown that excess belly fat and heart disease may be linked.

It has been hypothesized that the tendency for males to accumulate belly fats may account for their increased incidence of heart disease relative to the incidence of heart disease in women. As the most visible layer, subcutaneous adipose tissue is the type of fat most commonly targeted by those wishing to slim down. This type of fat may be measured with body calipers. Body calipers serve to estimate with reasonable accuracy the total percentage of one's mass that is composed of fats. This can be particularly useful in determining safe and healthy weight loss goals. Since fats are made up of stored energy, exercise has been found more effective at reducing adipose tissue than diet alone. While it is impossible to eliminate fat cells, it is possible to greatly reduce their size through appropriate eating and exercise habits.