Immunoglobulin A, an antibody class important at mucosal surfaces.
What it is
Serum IgA is one of the main antibody classes. Selective IgA deficiency is relatively common and often silent.
Why it matters
Very low or high IgA needs clinical context (infection history, gut, autoimmunity).
This guide is educational only and cannot diagnose you. Discuss results, especially anything outside your laboratory’s reference interval, or that does not match how you feel, with a GP or other appropriately qualified clinician.
How it affects the body
IgA helps defend mucosal surfaces in the gut and airways.
For athletes
Recurrent mucosal infections with low IgA deserve medical review rather than more training stress.
