What to watch with IgG and Sport?

When considering IgG (immunoglobulin G) in the context of sport, caution is warranted. IgG food sensitivity tests are popular in sports nutrition but lack robust scientific validation. Exercise can transiently lower IgG levels, potentially increasing infection risk, but measuring IgG to guide training or diet is not evidence-based. For performance optimization, focus on validated markers like testosterone, cortisol, ferritin, and vitamin D. The MyBody-X Body-Balance Test may provide hormone insights, but IgG-specific claims remain in the marketing realm. No controlled trials support genotype- or IgG-guided supplementation for athletes. Evidence: unclear/mixed. Sources: none from provided context.