A recent study from Saudi Arabia has established a connection between anxiety, insomnia, and reduced levels of natural killer (NK) cells in young women. The research, published in Frontiers in Immunology, highlights the potential implications of psychological stressors on the immune system, particularly among female students aged 17 to 23.
Natural killer cells play a critical role as the immune system’s first line of defense against pathogens and infected cells. When these cells are diminished, the body’s ability to combat disease may be compromised. The study, led by Dr. Renad Alhamawi of Taibah University, focused on understanding how anxiety and insomnia affect NK cell levels in young women.
Participants included 60 female students who completed surveys assessing their sociodemographics, anxiety symptoms, and insomnia. The findings revealed that approximately 53% of participants reported sleeping disturbances indicative of insomnia, while 75% experienced anxiety symptoms. Notably, 17% and 13% of the students reported moderate and severe anxiety symptoms, respectively.
Research Findings on NK Cells
The study employed blood samples to measure NK cell counts and their subtypes. Two key subtypes of NK cells were examined: CD16+CD56dim cells, which exhibit cytotoxic properties, and CD16+CD56high cells, which are involved in immunoregulation. Results indicated that students with insomnia symptoms exhibited a decrease in the number and percentage of total NK cells and their subtypes.
According to Dr. Alhamawi, “Students with general anxiety symptoms had a lower percentage and number of circulatory NK cells compared to symptom-free students.” Furthermore, the severity of anxiety symptoms correlated with a significant reduction in NK cell percentages, particularly among students with moderate to severe anxiety.
Implications for Health and Future Research
The implications of these findings are significant, as a reduction in NK cells can lead to immune system dysfunction, increasing the risk of diseases, including depression and various cancers. Dr. Alhamawi emphasized the importance of understanding how psychological stressors influence immune cell distribution, stating, “This may provide valuable insights into the mechanisms underlying inflammation and tumorigenesis.”
While the study offers valuable data, it is limited by its focus on a specific demographic group. The researchers acknowledged that the results may not be generalizable to all populations, suggesting that future studies should include diverse age groups, genders, and geographical locations to comprehensively examine the effects of anxiety and insomnia on immune function.
Previous research has indicated that a healthy lifestyle—encompassing regular physical activity, stress management, and a balanced diet—can enhance NK cell function. However, the current findings suggest that anxiety and insomnia can disrupt normal bodily functions, contributing to chronic and inflammatory diseases.
Dr. Alhamawi concluded, “Such impacts ultimately compromise overall health and quality of life,” underscoring the need for greater awareness and intervention strategies to support mental health and immune system functionality.
For further details, the study can be accessed through the DOI: 10.3389/fimmu.2025.1698155.
