Can excess or deficiency of biotin influence immune responses and allergy?

Biotin is a cofactor for carboxylases that affect metabolism and immune regulation, so its imbalance might modulate hypersensitivity.

Experimental data show that biotin deficiency in mice increases susceptibility to nickel contact hypersensitivity via elevated IL-1β production, whereas high serum biotin levels correlate weakly with increased total and specific IgE in children, suggesting both deficiency and excess can dysregulate immune responses and potentially promote allergy.