Garlic

What human studies say about garlic

• Blood pressure · Meta-analysis, 20 studies, 970 participants · 2016
  Garlic was associated with a mean systolic decrease of 5.1 mm Hg and diastolic decrease of 2.5 mm Hg versus placebo. Reductions were larger in hypertensive subgroups (systolic 8.7 mm Hg, diastolic 6.1 mm Hg). Limitation: Cholesterol and immunity sections were narrative reviews rather than new pooled analyses, and the blood pressure search used a single database (Medline). PubMed 26764326
• Common cold · Systematic review, 1 studies, 146 participants · 2014
  Only one trial met inclusion criteria. It reported fewer colds with garlic than with placebo (24 versus 65 occurrences), while days to recovery were similar. The authors concluded evidence was insufficient. Limitation: Only one trial qualified, and it relied on self-reported cold episodes, so firm conclusions cannot be drawn. PubMed 25386977
• Immune function, colds · Randomized controlled trial, 120 participants · 2016
  Gamma-delta T and NK cells proliferated better and were more activated than with placebo. The number of illnesses did not differ significantly, but cold and flu severity and missed days were lower. Limitation: Cold and flu outcomes were self-reported in daily diaries, and the dose was a concentrated extract that is not comparable to dietary garlic. PubMed 26764332

Most studies used extracts or doses that differ from home cooking. Full details in the Nourilo Research Library.