Garlic is a boost to any kitchen pantry, and outside your favorite dish it may also have some health benefit; it may help people get their blood pressure under control. Research suggests that garlic may ease hypertension. But if you're taking garlic supplements as a cold remedy, or for any other health benefit, you're probably out of luck.
Garlic contains a sulfur-containing compound called allicin, which may have both antibacterial and antiviral properties, and because of that the vegetable was adopted as potential way to prevent and treat against the hundreds of viruses that cause the common cold. Despite its popularity, though, there's little evidence that eating raw garlic, or taking supplements, can reduce the severity of your cold symptoms or the length of time you suffer your cold, culminating in a 2012 study that concluded more evidence is needed before anyone can claim with certainty garlic's role against rhinoviruses [source: Lissiman et al].