Supplementation with aged garlic extract improves both NK and γδ-T cell function and reduces the severity of cold and flu symptoms: a randomized, double-blind, placebo-controlled nutrition intervention.

BACKGROUND & AIMS: Earlier studies show that dietary bioactive compounds can modify proliferation of γδ-T cells. Garlic contains numerous compounds that have this potential and, in addition, has been shown to influence NK cell function. Our primary aim was to demonstrate that aged garlic extract could modify these immune cells.

METHODS: A randomized, double-blind, placebo-controlled parallel intervention study recruited 120 healthy subjects (60 per group) to determine the effect of aged garlic extract supplementation (2.56 g/d) on immune cell proliferation and cold and flu symptoms.