Healthy immune response includes the ability to accurately determine what is harmful to the body, adapt to changes in the environment, manage infections, and retain memory of what foreign cells cause damage.[1] One approach to quantifying immune health is by measuring biomarkers in blood that reflect each of these facets of the immune response. These biomarkers may include: leukocytes, lymphocytes, cytokines, T-cells, natural killer (NK) cells, monocytes, C-reactive protein, and antibodies. An important consideration here is that these biomarkers may be elevated as part of a healthy immune response, for example, to an infection. Concern may be warranted if there is an abnormally high level of inflammatory biomarkers or if they’ve been circulating at a higher than average level for an extended time.[2] [3]
Beyond blood tests, perceived immune status is a subjective assessment that may be more accessible to those outside of the clinical setting. The Immune Status Questionnaire (ISQ) was published in 2019, and is a validated self-assessment that may help individuals determine if they should seek medical attention, make lifestyle changes, or take further action to improve immune health.[4]