A recent study is researching the release of nerve growth factor, a molecule that promotes the survival and development of sensory and sympathetic neurons, in saliva.

Doug Granger, a psychology professor at Arizona State University and co-author of the study, said the findings could help scientists understand how the human body reacts to stress.

The study suggested there is a positive effect when higher levels of nerve growth factor are present during times of stress.

Granger said he tracked the release of NGF in saliva.

“Stress is an issues that on everybody’s mind," he said "Everybody is considered about that effect of stress on their wellbeing."

He said part of the puzzle is to figure out why people react differently to stress.

Granger said one of the goal's of his researcher is to use the information gained from biomarkers, such as NGF, and figuring out how to use it to help people.

Studying biological indicators in saliva is less invasive than drawing blood from a patient, he said.