Because the innate immune system, with its natural killer cells, is the body's first line of defense against cancer and pathogens, we're interested in everything that strengthens that first line of defense. We've previously written about sleep, stress, physical exercise, and edible mushrooms. Today, we're writing about music.

Study
In 2001, Japanese neurologists from Nagoya City Koseiin Geriatric Hospital published a small clinical study involving 19 nursing home residents. They had a variety of diagnoses, ranging from Alzheimer's and Parkinson's to post-stroke symptoms.

For 12 weeks, the residents received music therapy for one hour per week. This involved playing and listening to music under supervision.

Before the first session and after the last session, the researchers took blood samples from the residents. They extracted lymphocytes and determined the percentage of these lymphocytes that consisted of Natural Killer cells. They also measured the activity of the natural killer (NK) cells.

Results
After the music therapy, the NK cells had become 18 percent more active. Furthermore, the percentage of NK cells in their blood had increased by approximately 40 percent. There was no effect on B and T cells.

All subgroups in the study responded equally well to music.