This is the finding of a study on factors contributing to the likelihood of becoming ill conducted by Alison Smith, Ph.D., a research scientist working with a collaborative team from the universities of New South Wales and Western Sydney in Australia. Results of the study were presented for the first time at the American Psychosomatic Society Annual Meeting, held March 5-8 in Phoenix, Arizona.

The job of the body's immune system is to protect us from bacteria and viruses that cause many of our illnesses. In this research scientists examined how effectively the immune system was working when individuals were feeling miserable compared with those who felt fine.

Two hundred and fourteen participants were injected with a substance that normally produces an immune response. Results showed that greater levels of distress were accompanied by a reduced capacity to develop immunity, especially in those people who drank more alcohol at the time the time the measures were taken.

In the second part of the research, genetic factors that may protect individuals against particular bacteria or viruses were examined. Having one of these genes doubled the likelihood of not developing an immune response. Being distressed increased the likelihood of not developing a response five-fold. Furthermore, distress and genetic make-up combined to determine overall immunity. The researchers concluded that both distress and genes are likely to influence resistance to disease.