The phrase "immune functioning" refers to how well your immune system is working. It is a way to describe the ability of your body's defense system to fight off diseases and protect you from getting sick. Full definition
Taking zinc supplements by mouth is unlikely to improve immune function in people who are not at risk for zinc deficiency. (webmd.com)
To reduce fever; while this is a common use for humans, we recognize that fever has an important place in immune function in fighting infection. (vin.com)
These homemade herbal cough drops have a mixture of honey herbs to help alleviate symptoms and boost immune function for quick recovery. (wellnessmama.com)