Does ashwagandha affect immune health?

It is uncertain whether ashwagandha affects immune health by reducing stress, but chronic stress does tend to suppress healthy immune function.^[1][2][3] Ashwagandha’s general immunomodulatory capability (as exerted by 60–500 mg for 1–4 weeks) has been explored through direct assessment of immune parameters (immunoglobulins A, M, G, cytokines, natural killer cell content/activity, and lymphocytes) with encouraging results for fighting infection.^{[4][5][6][7][8][9]} These findings, however, still require replication with more robust methodological approaches.

When examining the prevention or treatment of respiratory infection, studies tended to take a more complete ayurvedic approach by using ashwagandha alongside additional therapies and/or herbs. While these studies indicate promising initial results, variation in methods and intervention used may need to be addressed before conclusions can be drawn or generalized.^{[5][10][11][8][9]}

Animal studies suggest that some of ashwagandha’s benefits for immune health may also be due to its antioxidant and anti-inflammatory properties.^[12] A few human clinical trials in adults with and without health conditions appear to reflect this possibility, too. Ashwagandha use (500–5,000 mg daily for 8–12 weeks) correlated with increases in antioxidants and decreases in oxidation markers such as malondialdehyde, along with improvements in exercise recovery, fertility, lung function, oxygen uptake, perceived stress signs and symptoms, and quality of life.^[13][14][15] Several studies have also explored ashwagandha for treating arthritis (500–1,000 mg daily for 8–12 weeks), where anti-inflammatory capacity was the proposed mechanism of action, though this mechanism and effect still has yet to be confirmed.^[16][17][18]