Garlic Supplement Review

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  Evaluated for:
Effectiveness Rating Effectiveness Rating
High blood pressure
+2 (Moderate Evidence)
High cholesterol
+2 (Moderate Evidence)


  • Garlic is an herb with modest benefits for lowering blood pressure and cholesterol.
  • Garlic appears to slow the progression of atherosclerosis of the aorta (hardening of the arteries).
  • Garlic is a source of polyphenols, which may reduce cancer risk and inflammation in the body.
  • Garlic taken regularly may prevent, and speed recovery from, viral upper respiratory infections.
  • Garlic may prevent stomach and colon cancer in populations with a high dietary intake.
  • Garlic may help control blood sugar control and manage diabetes.
  • Topical garlic cream has been studied to treat athlete’s foot and you may find that it helps.
  • Garlic is generally recognized as safe by the FDA.


  • Garlic may increase bleeding in patients taking blood thinners.
  • Garlic does not improve peripheral vascular disease.
  • Garlic does not necessarily prevent breast or lung cancer.
  • Garlic does not lower cholesterol for those with familial (genetic) high cholesterol.
  • Garlic can irritate the skin.
  • Garlic can cause unpleasant breath, a distinct smell on the body, stomach upset, nausea, vomiting, bloating and diarrhea. Some people think that the reason garlic is protective against colds is that the upper-respiratory viruses don’t like the smell either!

Do not use garlic, (or onions, leeks, chives or tulips) if you have a garlic allergy. Garlic interferes with HIV drugs (saquinavir and other antiplatelet drugs). People who take garlic regularly for medicinal reasons should notify their doctors and dentists, and discontinue use well before any planned surgical or dental procedures. Garlic may lower blood sugar and should be used with caution in patients on blood sugar lowering medications.

DOSAGE:1 clove (approximately 2g) once or twice daily, or 200-300 mg dried garlic powder three times daily, or 1-2 g aged garlic extract either two or three times daily.

CONCLUSION:We conclude that garlic is safe to use and can be an adjunct to medical treatment for high LDL cholesterol, elevated blood sugars, high blood pressure and for long term use in preventing viral upper respiratory infections. If you elect to try it, remember to include it in your list of medications when you visit your doctor and other health care providers.

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