Garlic
The evidence on garlic is real. The form on the label decides how much of it reaches you.
Garlic (Allium sativum) has been studied in a number of trials for modest reductions in blood pressure and cholesterol, and its most-cited active compound, allicin, only forms when the intact bulb is crushed and the alliinase enzyme meets its substrate alliin. Aged garlic extract, of which Kyolic is the branded form most trials use, is fermented over many months, which reduces the raw pungency and produces a more stable, water-soluble profile with the strongest trial evidence for cardiovascular endpoints. Standardised extracts guarantee an allicin yield on the label; garlic oil and dehydrated powder are cheaper but deliver less consistent active-compound content. Cooking garlic destroys most of the alliinase, which is why the raw-clove or supplement route is what the research is based on.
Forms and bioavailability
Not all forms are absorbed equally. The form on your supplement label affects how much your body can actually use.
| Form | Absorption | With food | Timing | Evidence |
|---|---|---|---|---|
| garlic powder (dehydrated) | Lower | With food | Either | Possible |
| garlic extract (standardised allicin) | Typical | With food | Either | Likely |
| garlic oil softgel | Typical | With food | Either | Possible |
| aged garlic extract (Kyolic) | Higher | With food | Either | Strong |
Stack Almanac tracks which garlic form you're taking, since aged extract and dehydrated powder are pursuing the same claim on the label with very different underlying chemistry.
Track your Garlic in Stack Almanac
Last reviewed: 2026-07-22. Reference values are adult-general RDAs. Individual needs may vary. This page is for informational purposes only and is not a substitute for professional medical advice.