Getting a massage might alter the body's immune response and lower stress-related hormones, a new U.S. study suggests.

In a small-scale study, the blood of 29 people who received 45-minute Swedish massages was tested five minutes and one minute before the massage began, then one, five, 10, 15, 30 and 60 minutes after the massage, using intravenous catheters.

Swedish massage is a form of massage originally used on gymnasts to relax tired and tense muscles.

The blood of people who received 45 minutes of light touch massage — a much less intense form of massage — was also tested, and saliva samples were taken from both groups.

The massage therapists all adhered to the same massage pattern and were audiotaped for quality control.

The researchers, from Cedars-Sinai Department of Psychiatry and Behavioural Neurosciences, a Los Angeles-based medical centre, found that the Swedish massages reduced arginine vasopressin, a hormone that causes the stress hormone cortisol to increase. The massages also reduced levels of cortisol itself in the body.

Study participants also saw their cytokines — proteins released by stimulated white blood cells when danger is present — decrease, indicating the body did not see itself as under attack during the massage.

Light touch recipients saw their cytokine levels actually rise slightly.

The researchers believe that massage could play a role in helping people manage inflammatory or autoimmune conditions, in which the body's immune system overreacts, attacking itself.

"This research indicates that massage doesn't only feel good, it also may be good for you," said Rapaport, the principal investigator of the study and the Polier Family Chair in Schizophrenia and Related Disorders, in a release. "More research is ahead of us, but it appears that a single massage may deliver a measurable benefit."

The authors believe a larger study should now be undertaken to replicate the results.

The study was published online Wednesday and will be published in the October issue of the Journal of Alternative and Complementary Medicine.