T-cells specifically earmark viral cells and other invaders for destruction. Zinc is vital to balancing T-cell function and therefore immune system response. Reishi mushroom has been shown to promote "significant beneficial changes in immune cells."(2)
Personal product favorite:
https://shorte.isagenix.com/en-us/products/vitality-well-being/individual/isamune-with-zinc
https://shorte.isagenix.com/en-us/products/vitality-well-being/individual/shake-booster-immune
Sources:
1. "Thymus." Wikipedia, The Free Encyclopedia. 13 Sep 2018. Web 5 Sep 2019. <https://simple.wikipedia.org/w/index.php?title=Thymus&oldid=6250624>.
2. "Why Isamune Plus with Zinc? Just in Time for Winter." Isagenix Health, Isagenix Worldwide, Inc., 3 November 2011, https://www.isagenixhealth.net/just-in-time-for-winter-introducing-new-isamune-plus-with-zinc/.