Fat can be a good thing, especially that belly fat you want to get rid of. According to a new study, belly fat may play an important role in regulating the immune system.

The fatty membrane that hangs from the stomach, called omentum, is found in all animals but was previously thought to be kind of useless in humans. The membrane lines organs found in the abdomen and acts as a storehouse for fat. While too much belly fat may be unsightly for some, there is an important reason why we have belly fat in the first place.

The study that helped uncovered belly fat's usefulness was led by Makio Iwashima, PhD, associate professor in the Department of Microbiology and Immunology at Loyola University Chicago Stritch School of Medicine. Researchers studied omentum cells of mice to determine if it had any effect on immune system response.

The researchers were looking to see if omentum had any effect on T-lymphocyte cells. T-cells are a very important part of the immune system response, usually acting as the first defense against bacteria. When T-cells recognize an infection or bacteria, the cells usually multiply to fight off the foreign body.

Omentum cells were introduced to T-cells that were active and producing more T-cells. Instead of continuing to multiply, the T-cells died. Omentum cells had no effect on inactive T-cells.

Researchers believe that the omentum is used to suppress immune system response and helps regulate the body's response to foreign bacteria. In the future, omentum cells may be used to help develop new drugs that would suppress the immune system but with fewer side effects than immune-suppressing drugs that are currently available.

Another interesting aspect of belly fat was its potential role in regenerating damaged tissue. Researchers discovered mesenchymal stem cells, which are used by the body to repair damaged tissue. The stem cells will travel to the site of the injury in order to repair damaged tissue which is vital for wound healing.

Instead of being a nuisance, belly fat may be quite useful to human survival. It can regulate immune system response, help heal wounds, repair damaged tissue and help create new tissue. For scientists, belly fat may be a buffet of new medical treatments for organ transplants and auto-immune diseases.

The study was published in PLoS ONE