TruImmuneBoost is an herbal formula that is designed to support healthy immune system function during cold and flu season.** It contains herbs that support normal natural killer (NK) cell activity and the balance of cytokines, which are the regulatory proteins released by immune cells as part of a normal immune system response.** The standardized herbs in this formula contain optimal and consistent amounts of the most active ingredients. TruImmuneBoost™ is suitable for long term use and for all age groups.