Garlic (Food Form) for Immune Function

Research suggests that the evidence specifically examining garlic's role in human immune function is limited and mixed. The most directly relevant human data comes from a large observational study of over 1.4 million people during the COVID-19 pandemic, which found no meaningful association between garlic supplementation and reduced risk of SARS-CoV-2 infection. One laboratory study found that allicin, an active compound in garlic, inhibited viral replication in cell cultures and appeared to counteract infection-related changes in lung cells, though the authors themselves noted this work has not been tested in humans and cell-based findings do not necessarily translate to clinical outcomes. The remaining studies in this evidence set examined unrelated topics such as cognitive decline, plant cell biology, and microbiome transmission in wild mice, and do not contribute meaningfully to understanding garlic's effects on human immune function, leaving the overall body of relevant evidence quite sparse and insufficient to draw firm conclusions.