Metabolite levels present in saliva can be used to diagnose Alzheimer's disease, according to new research.

The study was led by Shraddha Sapkota, a neuroscience graduate from University of Alberta, Canada, and a team of researchers, who presented their results on Sunday, during the Alzheimer's Association International Conference.

Researchers warn that the diagnostic test is still on its early stages. Even though the tests yielded accurate results, saliva still contains different substances and the study only involved a small group of participants.

For the study, researchers analyzed samples of saliva from 22 participants who have Alzheimer's, 25 participants with "mild cognitive impairment," and 35 participants who have normal cognitive function using a technique called liquid chromatography-mass spectrometry, as reported in Medical News Today.

The results were compared to clinical data taken from the Victoria Longitudinal Study. The researchers found that there were more known proteins noticeable among the participants diagnosed with Alzheimer's and mild cognitive impairment than in the healthy participants.

The team is hopeful that their discovery will hold the key to a promising diagnostic technique for Alzheimer's that is non-invasive and affordable. However, they stress that further studies are needed to determine the effectiveness of the saliva test.

Other clinicians also described the findings as promising but they insist that it's too early to jump into conclusions due to several variables that needed to be considered.

"This is a very preliminary study with a small number of subjects and the results are far from conclusive," Dr. Allison Reiss of Winthrop-University Hospital in Mineola, N.Y. told CBS News.

Currently, there exists no single diagnostic test that can predict a person's likelihood of developing Alzheimer's disease.

According to Medical News Today, diagnosing the disease requires a series of medical examinations, which include physical exams, cognitive function tests, and "mental status testing."

Most of the screening tests currently used are either expensive, invasive, or unreliable.