Evidence check: IgG in the context of Schlaf

The evidence linking IgG (immunoglobulin G) to sleep is weak. IgG is an antibody involved in immune memory, and while sleep deprivation can alter immune parameters, specific IgG levels are not a validated biomarker for sleep quality or disorders. No robust clinical studies support routine IgG testing for sleep issues. Direct-to-consumer wellness labs sometimes include IgG panels in their offerings, but the evidence base is limited: effect sizes are small, and results often lack clinical utility. Professional sleep societies (e.g., AASM, DGSM) do not recommend IgG testing for sleep complaints. Instead, validated tools like sleep diaries, actigraphy, or polysomnography should be used. Be cautious of marketing claims that overstate the role of IgG in sleep. If you have persistent sleep problems, consult a physician rather than relying on unproven lab tests.